---
_id: '14334'
abstract:
- lang: eng
text: Quantum kinetically constrained models have recently attracted significant
attention due to their anomalous dynamics and thermalization. In this work, we
introduce a hitherto unexplored family of kinetically constrained models featuring
conserved particle number and strong inversion-symmetry breaking due to facilitated
hopping. We demonstrate that these models provide a generic example of so-called
quantum Hilbert space fragmentation, that is manifested in disconnected sectors
in the Hilbert space that are not apparent in the computational basis. Quantum
Hilbert space fragmentation leads to an exponential in system size number of eigenstates
with exactly zero entanglement entropy across several bipartite cuts. These eigenstates
can be probed dynamically using quenches from simple initial product states. In
addition, we study the particle spreading under unitary dynamics launched from
the domain wall state, and find faster than diffusive dynamics at high particle
densities, that crosses over into logarithmically slow relaxation at smaller densities.
Using a classically simulable cellular automaton, we reproduce the logarithmic
dynamics observed in the quantum case. Our work suggests that particle conserving
constrained models with inversion symmetry breaking realize so far unexplored
dynamical behavior and invite their further theoretical and experimental studies.
acknowledgement: "We would like to thank Raimel A. Medina, Hansveer Singh, and Dmitry
Abanin for useful\r\ndiscussions.The authors acknowledge support by the European
Research Council\r\n(ERC) under the European Union’s Horizon 2020 research and innovation
program (Grant\r\nAgreement No. 850899). We acknowledge support by the Erwin Schrödinger
International\r\nInstitute for Mathematics and Physics (ESI)."
article_number: '093'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Pietro
full_name: Brighi, Pietro
id: 4115AF5C-F248-11E8-B48F-1D18A9856A87
last_name: Brighi
orcid: 0000-0002-7969-2729
- first_name: Marko
full_name: Ljubotina, Marko
id: F75EE9BE-5C90-11EA-905D-16643DDC885E
last_name: Ljubotina
orcid: 0000-0003-0038-7068
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: Brighi P, Ljubotina M, Serbyn M. Hilbert space fragmentation and slow dynamics
in particle-conserving quantum East models. SciPost Physics. 2023;15(3).
doi:10.21468/scipostphys.15.3.093
apa: Brighi, P., Ljubotina, M., & Serbyn, M. (2023). Hilbert space fragmentation
and slow dynamics in particle-conserving quantum East models. SciPost Physics.
SciPost Foundation. https://doi.org/10.21468/scipostphys.15.3.093
chicago: Brighi, Pietro, Marko Ljubotina, and Maksym Serbyn. “Hilbert Space Fragmentation
and Slow Dynamics in Particle-Conserving Quantum East Models.” SciPost Physics.
SciPost Foundation, 2023. https://doi.org/10.21468/scipostphys.15.3.093.
ieee: P. Brighi, M. Ljubotina, and M. Serbyn, “Hilbert space fragmentation and slow
dynamics in particle-conserving quantum East models,” SciPost Physics,
vol. 15, no. 3. SciPost Foundation, 2023.
ista: Brighi P, Ljubotina M, Serbyn M. 2023. Hilbert space fragmentation and slow
dynamics in particle-conserving quantum East models. SciPost Physics. 15(3), 093.
mla: Brighi, Pietro, et al. “Hilbert Space Fragmentation and Slow Dynamics in Particle-Conserving
Quantum East Models.” SciPost Physics, vol. 15, no. 3, 093, SciPost Foundation,
2023, doi:10.21468/scipostphys.15.3.093.
short: P. Brighi, M. Ljubotina, M. Serbyn, SciPost Physics 15 (2023).
date_created: 2023-09-14T13:08:23Z
date_published: 2023-09-13T00:00:00Z
date_updated: 2023-09-20T10:46:29Z
day: '13'
ddc:
- '530'
department:
- _id: MaSe
doi: 10.21468/scipostphys.15.3.093
ec_funded: 1
external_id:
arxiv:
- '2210.15607'
file:
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content_type: application/pdf
creator: dernst
date_created: 2023-09-20T10:46:10Z
date_updated: 2023-09-20T10:46:10Z
file_id: '14350'
file_name: 2023_SciPostPhysics_Brighi.pdf
file_size: 4866506
relation: main_file
success: 1
file_date_updated: 2023-09-20T10:46:10Z
has_accepted_license: '1'
intvolume: ' 15'
issue: '3'
keyword:
- General Physics and Astronomy
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
project:
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call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: SciPost Physics
publication_identifier:
issn:
- 2542-4653
publication_status: published
publisher: SciPost Foundation
quality_controlled: '1'
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relation: earlier_version
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status: public
title: Hilbert space fragmentation and slow dynamics in particle-conserving quantum
East models
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 15
year: '2023'
...
---
_id: '14622'
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Stefan
full_name: Sack, Stefan
id: dd622248-f6e0-11ea-865d-ce382a1c81a5
last_name: Sack
orcid: 0000-0001-5400-8508
citation:
ama: 'Sack S. Improving variational quantum algorithms: Innovative initialization
techniques and extensions to qudit systems. 2023. doi:10.15479/at:ista:14622'
apa: 'Sack, S. (2023). Improving variational quantum algorithms: Innovative initialization
techniques and extensions to qudit systems. Institute of Science and Technology
Austria. https://doi.org/10.15479/at:ista:14622'
chicago: 'Sack, Stefan. “Improving Variational Quantum Algorithms: Innovative Initialization
Techniques and Extensions to Qudit Systems.” Institute of Science and Technology
Austria, 2023. https://doi.org/10.15479/at:ista:14622.'
ieee: 'S. Sack, “Improving variational quantum algorithms: Innovative initialization
techniques and extensions to qudit systems,” Institute of Science and Technology
Austria, 2023.'
ista: 'Sack S. 2023. Improving variational quantum algorithms: Innovative initialization
techniques and extensions to qudit systems. Institute of Science and Technology
Austria.'
mla: 'Sack, Stefan. Improving Variational Quantum Algorithms: Innovative Initialization
Techniques and Extensions to Qudit Systems. Institute of Science and Technology
Austria, 2023, doi:10.15479/at:ista:14622.'
short: 'S. Sack, Improving Variational Quantum Algorithms: Innovative Initialization
Techniques and Extensions to Qudit Systems, Institute of Science and Technology
Austria, 2023.'
date_created: 2023-11-28T10:58:13Z
date_published: 2023-11-30T00:00:00Z
date_updated: 2023-12-13T14:47:25Z
day: '30'
ddc:
- '530'
degree_awarded: PhD
department:
- _id: GradSch
- _id: MaSe
doi: 10.15479/at:ista:14622
ec_funded: 1
file:
- access_level: closed
checksum: 068fd3570506ec42b2faa390de784bc4
content_type: application/pdf
creator: ssack
date_created: 2023-11-30T15:53:10Z
date_updated: 2023-12-01T11:10:46Z
embargo: 2024-11-30
embargo_to: open_access
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file_name: PhD_Thesis.pdf
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file_size: 18422964
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has_accepted_license: '1'
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc-sa/4.0/
month: '11'
oa_version: Published Version
page: '142'
project:
- _id: bd660c93-d553-11ed-ba76-fb0fb6f49c0d
name: Quantum_Quantum Circuits and Software_Variational quantum algorithms on NISQ
devices
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication_identifier:
issn:
- 2663 - 337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '11471'
relation: part_of_dissertation
status: public
- id: '13125'
relation: part_of_dissertation
status: public
- id: '9760'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
title: 'Improving variational quantum algorithms: Innovative initialization techniques
and extensions to qudit systems'
tmp:
image: /images/cc_by_nc_sa.png
legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode
name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC
BY-NC-SA 4.0)
short: CC BY-NC-SA (4.0)
type: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2023'
...
---
_id: '13125'
abstract:
- lang: eng
text: 'The quantum approximate optimization algorithm (QAOA) is a variational quantum
algorithm, where a quantum computer implements a variational ansatz consisting
of p layers of alternating unitary operators and a classical computer is used
to optimize the variational parameters. For a random initialization, the optimization
typically leads to local minima with poor performance, motivating the search for
initialization strategies of QAOA variational parameters. Although numerous heuristic
initializations exist, an analytical understanding and performance guarantees
for large p remain evasive.We introduce a greedy initialization of QAOA which
guarantees improving performance with an increasing number of layers. Our main
result is an analytic construction of 2p + 1 transition states—saddle points with
a unique negative curvature direction—for QAOA with p + 1 layers that use the
local minimum of QAOA with p layers. Transition states connect to new local minima,
which are guaranteed to lower the energy compared to the minimum found for p layers.
We use the GREEDY procedure to navigate the exponentially increasing with p number
of local minima resulting from the recursive application of our analytic construction.
The performance of the GREEDY procedure matches available initialization strategies
while providing a guarantee for the minimal energy to decrease with an increasing
number of layers p. '
acknowledgement: 'We thank V. Verteletskyi for a joint collaboration on numerical
studies of the QAOA during his internship at ISTA that inspired analytic results
on TS reported in this work. We acknowledge A. A. Mele and M. Brooks for discussions
and D. Egger, P. Love, and D. Wierichs for valuable feedback on the manuscript.
S.H.S., R.A.M., and M.S. acknowledge support by the European Research Council (ERC)
under the European Union’s Horizon 2020 research and innovation program (Grant Agreement
No. 850899). R.K. is supported by the SFB BeyondC (Grant No. F7107-N38) and the
project QuantumReady (FFG 896217). '
article_number: '062404'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Stefan
full_name: Sack, Stefan
id: dd622248-f6e0-11ea-865d-ce382a1c81a5
last_name: Sack
orcid: 0000-0001-5400-8508
- first_name: Raimel A
full_name: Medina Ramos, Raimel A
id: CE680B90-D85A-11E9-B684-C920E6697425
last_name: Medina Ramos
orcid: 0000-0002-5383-2869
- first_name: Richard
full_name: Kueng, Richard
last_name: Kueng
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: Sack S, Medina Ramos RA, Kueng R, Serbyn M. Recursive greedy initialization
of the quantum approximate optimization algorithm with guaranteed improvement.
Physical Review A. 2023;107(6). doi:10.1103/physreva.107.062404
apa: Sack, S., Medina Ramos, R. A., Kueng, R., & Serbyn, M. (2023). Recursive
greedy initialization of the quantum approximate optimization algorithm with guaranteed
improvement. Physical Review A. American Physical Society. https://doi.org/10.1103/physreva.107.062404
chicago: Sack, Stefan, Raimel A Medina Ramos, Richard Kueng, and Maksym Serbyn.
“Recursive Greedy Initialization of the Quantum Approximate Optimization Algorithm
with Guaranteed Improvement.” Physical Review A. American Physical Society,
2023. https://doi.org/10.1103/physreva.107.062404.
ieee: S. Sack, R. A. Medina Ramos, R. Kueng, and M. Serbyn, “Recursive greedy initialization
of the quantum approximate optimization algorithm with guaranteed improvement,”
Physical Review A, vol. 107, no. 6. American Physical Society, 2023.
ista: Sack S, Medina Ramos RA, Kueng R, Serbyn M. 2023. Recursive greedy initialization
of the quantum approximate optimization algorithm with guaranteed improvement.
Physical Review A. 107(6), 062404.
mla: Sack, Stefan, et al. “Recursive Greedy Initialization of the Quantum Approximate
Optimization Algorithm with Guaranteed Improvement.” Physical Review A,
vol. 107, no. 6, 062404, American Physical Society, 2023, doi:10.1103/physreva.107.062404.
short: S. Sack, R.A. Medina Ramos, R. Kueng, M. Serbyn, Physical Review A 107 (2023).
date_created: 2023-06-07T06:57:32Z
date_published: 2023-06-02T00:00:00Z
date_updated: 2023-12-13T14:47:25Z
day: '02'
ddc:
- '530'
department:
- _id: MaSe
doi: 10.1103/physreva.107.062404
ec_funded: 1
external_id:
arxiv:
- '2209.01159'
isi:
- '001016927100012'
file:
- access_level: open_access
checksum: 0d71423888eeccaa60d8f41197f26306
content_type: application/pdf
creator: dernst
date_created: 2023-06-13T07:28:36Z
date_updated: 2023-06-13T07:28:36Z
file_id: '13131'
file_name: 2023_PhysRevA_Sack.pdf
file_size: 2524611
relation: main_file
success: 1
file_date_updated: 2023-06-13T07:28:36Z
has_accepted_license: '1'
intvolume: ' 107'
isi: 1
issue: '6'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review A
publication_identifier:
eissn:
- 2469-9934
issn:
- 2469-9926
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
related_material:
record:
- id: '14622'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Recursive greedy initialization of the quantum approximate optimization algorithm
with guaranteed improvement
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 107
year: '2023'
...
---
_id: '13963'
abstract:
- lang: eng
text: The many-body localization (MBL) proximity effect is an intriguing phenomenon
where a thermal bath localizes due to the interaction with a disordered system.
The interplay of thermal and nonergodic behavior in these systems gives rise to
a rich phase diagram, whose exploration is an active field of research. In this
paper, we study a bosonic Hubbard model featuring two particle species representing
the bath and the disordered system. Using state-of-the-art numerical techniques,
we investigate the dynamics of the model in different regimes, based on which
we obtain a tentative phase diagram as a function of coupling strength and bath
size. When the bath is composed of a single particle, we observe clear signatures
of a transition from an MBL proximity effect to a delocalized phase. Increasing
the bath size, however, its thermalizing effect becomes stronger and eventually
the whole system delocalizes in the range of moderate interaction strengths studied.
In this regime, we characterize particle transport, revealing diffusive behavior
of the originally localized bosons.
acknowledgement: "We thank A. A. Michailidis and A. Mirlin for insightful discussions.
P.B., M.L., and M.S. acknowledge support by the European Research Council (ERC)
under the European Union’s Horizon 2020 research and innovation program (Grant Agreement
No. 850899). D.A. was\r\nsupported by the European Research Council (ERC) under
the European Union’s Horizon 2020 research and innovation program (Grant Agreement
No. 864597) and by the Swiss National Science Foundation. P.B., M.L., and M.S. acknowledge
PRACE for awarding us access to Joliot-Curie at GENCI@CEA, France, where the TEBD
simulations were performed. The TEBD simulations were performed using the ITensor
library [60]."
article_number: '054201'
article_processing_charge: Yes (in subscription journal)
article_type: original
arxiv: 1
author:
- first_name: Pietro
full_name: Brighi, Pietro
id: 4115AF5C-F248-11E8-B48F-1D18A9856A87
last_name: Brighi
orcid: 0000-0002-7969-2729
- first_name: Marko
full_name: Ljubotina, Marko
id: F75EE9BE-5C90-11EA-905D-16643DDC885E
last_name: Ljubotina
- first_name: Dmitry A.
full_name: Abanin, Dmitry A.
last_name: Abanin
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: Brighi P, Ljubotina M, Abanin DA, Serbyn M. Many-body localization proximity
effect in a two-species bosonic Hubbard model. Physical Review B. 2023;108(5).
doi:10.1103/physrevb.108.054201
apa: Brighi, P., Ljubotina, M., Abanin, D. A., & Serbyn, M. (2023). Many-body
localization proximity effect in a two-species bosonic Hubbard model. Physical
Review B. American Physical Society. https://doi.org/10.1103/physrevb.108.054201
chicago: Brighi, Pietro, Marko Ljubotina, Dmitry A. Abanin, and Maksym Serbyn. “Many-Body
Localization Proximity Effect in a Two-Species Bosonic Hubbard Model.” Physical
Review B. American Physical Society, 2023. https://doi.org/10.1103/physrevb.108.054201.
ieee: P. Brighi, M. Ljubotina, D. A. Abanin, and M. Serbyn, “Many-body localization
proximity effect in a two-species bosonic Hubbard model,” Physical Review B,
vol. 108, no. 5. American Physical Society, 2023.
ista: Brighi P, Ljubotina M, Abanin DA, Serbyn M. 2023. Many-body localization proximity
effect in a two-species bosonic Hubbard model. Physical Review B. 108(5), 054201.
mla: Brighi, Pietro, et al. “Many-Body Localization Proximity Effect in a Two-Species
Bosonic Hubbard Model.” Physical Review B, vol. 108, no. 5, 054201, American
Physical Society, 2023, doi:10.1103/physrevb.108.054201.
short: P. Brighi, M. Ljubotina, D.A. Abanin, M. Serbyn, Physical Review B 108 (2023).
date_created: 2023-08-05T18:25:22Z
date_published: 2023-08-01T00:00:00Z
date_updated: 2023-08-07T09:51:39Z
day: '01'
ddc:
- '530'
department:
- _id: MaSe
doi: 10.1103/physrevb.108.054201
ec_funded: 1
external_id:
arxiv:
- '2303.16876'
file:
- access_level: open_access
checksum: f763000339b5fd543c14377109920690
content_type: application/pdf
creator: dernst
date_created: 2023-08-07T09:48:08Z
date_updated: 2023-08-07T09:48:08Z
file_id: '13981'
file_name: 2023_PhysRevB_Brighi.pdf
file_size: 3051398
relation: main_file
success: 1
file_date_updated: 2023-08-07T09:48:08Z
has_accepted_license: '1'
intvolume: ' 108'
issue: '5'
language:
- iso: eng
month: '08'
oa: 1
oa_version: Published Version
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review B
publication_identifier:
eissn:
- 2469-9969
issn:
- 2469-9950
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Many-body localization proximity effect in a two-species bosonic Hubbard model
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 108
year: '2023'
...
---
_id: '12732'
abstract:
- lang: eng
text: "Nonergodic systems, whose out-of-equilibrium dynamics fail to thermalize,
provide a fascinating research direction both for fundamental reasons and for
application in state of the art quantum devices.\r\nGoing beyond the description
of statistical mechanics, ergodicity breaking yields a new paradigm in quantum
many-body physics, introducing novel phases of matter with no counterpart at equilibrium.\r\nIn
this Thesis, we address different open questions in the field, focusing on disorder-induced
many-body localization (MBL) and on weak ergodicity breaking in kinetically constrained
models.\r\nIn particular, we contribute to the debate about transport in kinetically
constrained models, studying the effect of $U(1)$ conservation and inversion-symmetry
breaking in a family of quantum East models.\r\nUsing tensor network techniques,
we analyze the dynamics of large MBL systems beyond the limit of exact numerical
methods.\r\nIn this setting, we approach the debated topic of the coexistence
of localized and thermal eigenstates separated by energy thresholds known as many-body
mobility edges.\r\nInspired by recent experiments, our work further investigates
the localization of a small bath induced by the coupling to a large localized
chain, the so-called MBL proximity effect.\r\n\r\nIn the first Chapter, we introduce
a family of particle-conserving kinetically constrained models, inspired by the
quantum East model.\r\nThe system we study features strong inversion-symmetry
breaking, due to the nature of the correlated hopping.\r\nWe show that these models
host so-called quantum Hilbert space fragmentation, consisting of disconnected
subsectors in an entangled basis, and further provide an analytical description
of this phenomenon.\r\nWe further probe its effect on dynamics of simple product
states, showing revivals in fidelity and local observalbes.\r\nThe study of dynamics
within the largest subsector reveals an anomalous transient superdiffusive behavior
crossing over to slow logarithmic dynamics at later times.\r\nThis work suggests
that particle conserving constrained models with inversion-symmetry breaking realize
new universality classes of dynamics and invite their further theoretical and
experimental studies.\r\n\r\nNext, we use kinetic constraints and disorder to
design a model with many-body mobility edges in particle density.\r\nThis feature
allows to study the dynamics of localized and thermal states in large systems
beyond the limitations of previous studies.\r\nThe time-evolution shows typical
signatures of localization at small densities, replaced by thermal behavior at
larger densities.\r\nOur results provide evidence in favor of the stability of
many-body mobility edges, which was recently challenged by a theoretical argument.\r\nTo
support our findings, we probe the mechanism proposed as a cause of delocalization
in many-body localized systems with mobility edges suggesting its ineffectiveness
in the model studied.\r\n\r\nIn the last Chapter of this Thesis, we address the
topic of many-body localization proximity effect.\r\nWe study a model inspired
by recent experiments, featuring Anderson localized coupled to a small bath of
free hard-core bosons.\r\nThe interaction among the two particle species results
in non-trivial dynamics, which we probe using tensor network techniques.\r\nOur
simulations show convincing evidence of many-body localization proximity effect
when the bath is composed by a single free particle and interactions are strong.\r\nWe
furthter observe an anomalous entanglement dynamics, which we explain through
a phenomenological theory.\r\nFinally, we extract highly excited eigenstates of
large systems, providing supplementary evidence in favor of our findings."
acknowledged_ssus:
- _id: ScienComp
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Pietro
full_name: Brighi, Pietro
id: 4115AF5C-F248-11E8-B48F-1D18A9856A87
last_name: Brighi
orcid: 0000-0002-7969-2729
citation:
ama: Brighi P. Ergodicity breaking in disordered and kinetically constrained quantum
many-body systems. 2023. doi:10.15479/at:ista:12732
apa: Brighi, P. (2023). Ergodicity breaking in disordered and kinetically constrained
quantum many-body systems. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12732
chicago: Brighi, Pietro. “Ergodicity Breaking in Disordered and Kinetically Constrained
Quantum Many-Body Systems.” Institute of Science and Technology Austria, 2023.
https://doi.org/10.15479/at:ista:12732.
ieee: P. Brighi, “Ergodicity breaking in disordered and kinetically constrained
quantum many-body systems,” Institute of Science and Technology Austria, 2023.
ista: Brighi P. 2023. Ergodicity breaking in disordered and kinetically constrained
quantum many-body systems. Institute of Science and Technology Austria.
mla: Brighi, Pietro. Ergodicity Breaking in Disordered and Kinetically Constrained
Quantum Many-Body Systems. Institute of Science and Technology Austria, 2023,
doi:10.15479/at:ista:12732.
short: P. Brighi, Ergodicity Breaking in Disordered and Kinetically Constrained
Quantum Many-Body Systems, Institute of Science and Technology Austria, 2023.
date_created: 2023-03-17T13:30:48Z
date_published: 2023-03-21T00:00:00Z
date_updated: 2023-09-20T10:44:12Z
day: '21'
ddc:
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degree_awarded: PhD
department:
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- _id: MaSe
doi: 10.15479/at:ista:12732
ec_funded: 1
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file_date_updated: 2023-03-23T16:43:14Z
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language:
- iso: eng
month: '03'
oa: 1
oa_version: None
page: '158'
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '11470'
relation: part_of_dissertation
status: public
- id: '8308'
relation: part_of_dissertation
status: public
- id: '11469'
relation: part_of_dissertation
status: public
- id: '12750'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
title: Ergodicity breaking in disordered and kinetically constrained quantum many-body
systems
tmp:
image: /images/cc_by_nc_sa.png
legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode
name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC
BY-NC-SA 4.0)
short: CC BY-NC-SA (4.0)
type: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2023'
...
---
_id: '12839'
abstract:
- lang: eng
text: Universal nonequilibrium properties of isolated quantum systems are typically
probed by studying transport of conserved quantities, such as charge or spin,
while transport of energy has received considerably less attention. Here, we study
infinite-temperature energy transport in the kinetically constrained PXP model
describing Rydberg atom quantum simulators. Our state-of-the-art numerical simulations,
including exact diagonalization and time-evolving block decimation methods, reveal
the existence of two distinct transport regimes. At moderate times, the energy-energy
correlation function displays periodic oscillations due to families of eigenstates
forming different su(2) representations hidden within the spectrum. These families
of eigenstates generalize the quantum many-body scarred states found in previous
works and leave an imprint on the infinite-temperature energy transport. At later
times, we observe a long-lived superdiffusive transport regime that we attribute
to the proximity of a nearby integrable point. While generic strong deformations
of the PXP model indeed restore diffusive transport, adding a strong chemical
potential intriguingly gives rise to a well-converged superdiffusive exponent
z≈3/2. Our results suggest constrained models to be potential hosts of novel transport
regimes and call for developing an analytic understanding of their energy transport.
acknowledgement: "We would like to thank Alexios Michailidis, Sarang Gopalakrishnan,
and Achilleas Lazarides for useful comments. M. L. and M. S. acknowledge support
by the European Research Council under the European Union’s Horizon 2020 research
and innovation program (Grant\r\nAgreement No. 850899). J.-Y. D. and Z. P. acknowledge
support by EPSRC Grant No. EP/R513258/1 and the Leverhulme Trust Research Leadership
Grant No. RL2019-015. Statement of compliance with EPSRC policy framework on research
data: This publication is theoretical work that does not require supporting research
data. M. S., M. L., and Z. P. acknowledge support by the Erwin Schrödinger International
Institute for Mathematics and\r\nPhysics. M. L. and M. S. acknowledge PRACE for
awarding us access to Joliot-Curie at GENCI@CEA, France, where the TEBD simulations
were performed. The TEBD\r\nsimulations were performed using the ITENSOR library
[54]."
article_number: '011033'
article_processing_charge: No
article_type: original
author:
- first_name: Marko
full_name: Ljubotina, Marko
id: F75EE9BE-5C90-11EA-905D-16643DDC885E
last_name: Ljubotina
- first_name: Jean Yves
full_name: Desaules, Jean Yves
last_name: Desaules
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
- first_name: Zlatko
full_name: Papić, Zlatko
last_name: Papić
citation:
ama: Ljubotina M, Desaules JY, Serbyn M, Papić Z. Superdiffusive energy transport
in kinetically constrained models. Physical Review X. 2023;13(1). doi:10.1103/PhysRevX.13.011033
apa: Ljubotina, M., Desaules, J. Y., Serbyn, M., & Papić, Z. (2023). Superdiffusive
energy transport in kinetically constrained models. Physical Review X.
American Physical Society. https://doi.org/10.1103/PhysRevX.13.011033
chicago: Ljubotina, Marko, Jean Yves Desaules, Maksym Serbyn, and Zlatko Papić.
“Superdiffusive Energy Transport in Kinetically Constrained Models.” Physical
Review X. American Physical Society, 2023. https://doi.org/10.1103/PhysRevX.13.011033.
ieee: M. Ljubotina, J. Y. Desaules, M. Serbyn, and Z. Papić, “Superdiffusive energy
transport in kinetically constrained models,” Physical Review X, vol. 13,
no. 1. American Physical Society, 2023.
ista: Ljubotina M, Desaules JY, Serbyn M, Papić Z. 2023. Superdiffusive energy transport
in kinetically constrained models. Physical Review X. 13(1), 011033.
mla: Ljubotina, Marko, et al. “Superdiffusive Energy Transport in Kinetically Constrained
Models.” Physical Review X, vol. 13, no. 1, 011033, American Physical Society,
2023, doi:10.1103/PhysRevX.13.011033.
short: M. Ljubotina, J.Y. Desaules, M. Serbyn, Z. Papić, Physical Review X 13 (2023).
date_created: 2023-04-16T22:01:09Z
date_published: 2023-03-07T00:00:00Z
date_updated: 2023-08-01T14:11:28Z
day: '07'
ddc:
- '530'
department:
- _id: MaSe
doi: 10.1103/PhysRevX.13.011033
ec_funded: 1
external_id:
isi:
- '000957625700001'
file:
- access_level: open_access
checksum: ee060cea609af79bba7af74b1ce28078
content_type: application/pdf
creator: dernst
date_created: 2023-04-17T08:36:53Z
date_updated: 2023-04-17T08:36:53Z
file_id: '12845'
file_name: 2023_PhysReviewX_Ljubotina.pdf
file_size: 1958523
relation: main_file
success: 1
file_date_updated: 2023-04-17T08:36:53Z
has_accepted_license: '1'
intvolume: ' 13'
isi: 1
issue: '1'
language:
- iso: eng
month: '03'
oa: 1
oa_version: Published Version
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review X
publication_identifier:
eissn:
- 2160-3308
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Superdiffusive energy transport in kinetically constrained models
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 13
year: '2023'
...
---
_id: '11337'
abstract:
- lang: eng
text: 'Nonanalytic points in the return probability of a quantum state as a function
of time, known as dynamical quantum phase transitions (DQPTs), have received great
attention in recent years, but the understanding of their mechanism is still incomplete.
In our recent work [Phys. Rev. Lett. 126, 040602 (2021)], we demonstrated that
one-dimensional DQPTs can be produced by two distinct mechanisms, namely semiclassical
precession and entanglement generation, leading to the definition of precession
(pDQPTs) and entanglement (eDQPTs) dynamical quantum phase transitions. In this
manuscript, we extend and investigate the notion of p- and eDQPTs in two-dimensional
systems by considering semi-infinite ladders of varying width. For square lattices,
we find that pDQPTs and eDQPTs persist and are characterized by similar phenomenology
as in 1D: pDQPTs are associated with a magnetization sign change and a wide entanglement
gap, while eDQPTs correspond to suppressed local observables and avoided crossings
in the entanglement spectrum. However, DQPTs show higher sensitivity to the ladder
width and other details, challenging the extrapolation to the thermodynamic limit
especially for eDQPTs. Moving to honeycomb lattices, we also demonstrate that
lattices with an odd number of nearest neighbors give rise to phenomenologies
beyond the one-dimensional classification.'
acknowledgement: "We acknowledge support by the European Research Council (ERC) under
the European Union’s Horizon 2020 research and innovation programme (Grant Agreement
No. 850899).\r\nS.D.N. also acknowledges funding from the Institute of Science and
Technology (IST) Austria, and from the European Union’s Horizon 2020 Research and
Innovation Programme under the Marie Skłodowska-Curie Grant Agreement No. 754411."
article_number: '165149'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Stefano
full_name: De Nicola, Stefano
id: 42832B76-F248-11E8-B48F-1D18A9856A87
last_name: De Nicola
orcid: 0000-0002-4842-6671
- first_name: Alexios
full_name: Michailidis, Alexios
id: 36EBAD38-F248-11E8-B48F-1D18A9856A87
last_name: Michailidis
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: De Nicola S, Michailidis A, Serbyn M. Entanglement and precession in two-dimensional
dynamical quantum phase transitions. Physical Review B. 2022;105. doi:10.1103/PhysRevB.105.165149
apa: De Nicola, S., Michailidis, A., & Serbyn, M. (2022). Entanglement and precession
in two-dimensional dynamical quantum phase transitions. Physical Review B.
American Physical Society. https://doi.org/10.1103/PhysRevB.105.165149
chicago: De Nicola, Stefano, Alexios Michailidis, and Maksym Serbyn. “Entanglement
and Precession in Two-Dimensional Dynamical Quantum Phase Transitions.” Physical
Review B. American Physical Society, 2022. https://doi.org/10.1103/PhysRevB.105.165149.
ieee: S. De Nicola, A. Michailidis, and M. Serbyn, “Entanglement and precession
in two-dimensional dynamical quantum phase transitions,” Physical Review B,
vol. 105. American Physical Society, 2022.
ista: De Nicola S, Michailidis A, Serbyn M. 2022. Entanglement and precession in
two-dimensional dynamical quantum phase transitions. Physical Review B. 105, 165149.
mla: De Nicola, Stefano, et al. “Entanglement and Precession in Two-Dimensional
Dynamical Quantum Phase Transitions.” Physical Review B, vol. 105, 165149,
American Physical Society, 2022, doi:10.1103/PhysRevB.105.165149.
short: S. De Nicola, A. Michailidis, M. Serbyn, Physical Review B 105 (2022).
date_created: 2022-04-28T08:06:10Z
date_published: 2022-04-15T00:00:00Z
date_updated: 2023-08-03T06:33:33Z
day: '15'
department:
- _id: MaSe
doi: 10.1103/PhysRevB.105.165149
ec_funded: 1
external_id:
arxiv:
- '2112.11273'
isi:
- '000806812400004'
intvolume: ' 105'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: ' https://doi.org/10.48550/arXiv.2112.11273'
month: '04'
oa: 1
oa_version: Preprint
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
publication: Physical Review B
publication_identifier:
eisbn:
- 2469-9969
issn:
- 2469-9950
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: Entanglement and precession in two-dimensional dynamical quantum phase transitions
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 105
year: '2022'
...
---
_id: '11469'
abstract:
- lang: eng
text: Thermalizing and localized many-body quantum systems present two distinct
dynamical phases of matter. Recently the fate of a localized system coupled to
a thermalizing system viewed as a quantum bath received significant theoretical
and experimental attention. In this work, we study a mobile impurity, representing
a small quantum bath, that interacts locally with an Anderson insulator with a
finite density of localized particles. Using static Hartree approximation to obtain
an effective disorder strength, we formulate an analytic criterion for the perturbative
stability of the localization. Next, we use an approximate dynamical Hartree method
and the quasi-exact time-evolved block decimation (TEBD) algorithm to study the
dynamics of the system. We find that the dynamical Hartree approach which completely
ignores entanglement between the impurity and localized particles predicts the
delocalization of the system. In contrast, the full numerical simulation of the
unitary dynamics with TEBD suggests the stability of localization on numerically
accessible timescales. Finally, using an extension of the density matrix renormalization
group algorithm to excited states (DMRG-X), we approximate the highly excited
eigenstates of the system. We find that the impurity remains localized in the
eigenstates and entanglement is enhanced in a finite region around the position
of the impurity, confirming the dynamical predictions. Dynamics and the DMRG-X
results provide compelling evidence for the stability of localization.
acknowledged_ssus:
- _id: ScienComp
acknowledgement: We thank M. Ljubotina for insightful discussions. P. B., A. M. and
M. S. acknowledge support by the European Research Council (ERC) under the European
Union’s Horizon 2020 research and innovation program (Grant Agreement No. 850899).
D. A. was supported by the Swiss National Science Foundation and by the European
Research Council (ERC) under the European Union’s Horizon 2020 research and innovation
program (Grant Agreement No. 864597). The development of parallel TEBD code was
supported by S. Elefante from the Scientific Computing (SciComp) that is part of
Scientific Service Units (SSU) of IST Austria. Some of the computations were performed
on the Baobab cluster of the University of Geneva.
article_number: '224208'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Pietro
full_name: Brighi, Pietro
id: 4115AF5C-F248-11E8-B48F-1D18A9856A87
last_name: Brighi
orcid: 0000-0002-7969-2729
- first_name: Alexios
full_name: Michailidis, Alexios
id: 36EBAD38-F248-11E8-B48F-1D18A9856A87
last_name: Michailidis
orcid: 0000-0002-8443-1064
- first_name: Kristina
full_name: Kirova, Kristina
id: 4aeda2ae-f847-11ec-98e0-c4a66fe174d4
last_name: Kirova
- first_name: Dmitry A.
full_name: Abanin, Dmitry A.
last_name: Abanin
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: Brighi P, Michailidis A, Kirova K, Abanin DA, Serbyn M. Localization of a mobile
impurity interacting with an Anderson insulator. Physical Review B. 2022;105(22).
doi:10.1103/physrevb.105.224208
apa: Brighi, P., Michailidis, A., Kirova, K., Abanin, D. A., & Serbyn, M. (2022).
Localization of a mobile impurity interacting with an Anderson insulator. Physical
Review B. American Physical Society. https://doi.org/10.1103/physrevb.105.224208
chicago: Brighi, Pietro, Alexios Michailidis, Kristina Kirova, Dmitry A. Abanin,
and Maksym Serbyn. “Localization of a Mobile Impurity Interacting with an Anderson
Insulator.” Physical Review B. American Physical Society, 2022. https://doi.org/10.1103/physrevb.105.224208.
ieee: P. Brighi, A. Michailidis, K. Kirova, D. A. Abanin, and M. Serbyn, “Localization
of a mobile impurity interacting with an Anderson insulator,” Physical Review
B, vol. 105, no. 22. American Physical Society, 2022.
ista: Brighi P, Michailidis A, Kirova K, Abanin DA, Serbyn M. 2022. Localization
of a mobile impurity interacting with an Anderson insulator. Physical Review B.
105(22), 224208.
mla: Brighi, Pietro, et al. “Localization of a Mobile Impurity Interacting with
an Anderson Insulator.” Physical Review B, vol. 105, no. 22, 224208, American
Physical Society, 2022, doi:10.1103/physrevb.105.224208.
short: P. Brighi, A. Michailidis, K. Kirova, D.A. Abanin, M. Serbyn, Physical Review
B 105 (2022).
date_created: 2022-06-29T20:19:51Z
date_published: 2022-06-27T00:00:00Z
date_updated: 2023-09-05T12:12:52Z
day: '27'
department:
- _id: MaSe
doi: 10.1103/physrevb.105.224208
ec_funded: 1
external_id:
arxiv:
- '2111.08603'
isi:
- '000823050000001'
intvolume: ' 105'
isi: 1
issue: '22'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: ' https://doi.org/10.48550/arXiv.2111.08603 Focus to learn more'
month: '06'
oa: 1
oa_version: Preprint
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review B
publication_identifier:
eissn:
- 2469-9969
issn:
- 2469-9950
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
related_material:
record:
- id: '12732'
relation: dissertation_contains
status: public
status: public
title: Localization of a mobile impurity interacting with an Anderson insulator
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 105
year: '2022'
...
---
_id: '11470'
abstract:
- lang: eng
text: Many-body localization (MBL) is an example of a dynamical phase of matter
that avoids thermalization. While the MBL phase is robust to weak local perturbations,
the fate of an MBL system coupled to a thermalizing quantum system that represents
a “heat bath” is an open question that is actively investigated theoretically
and experimentally. In this work, we consider the stability of an Anderson insulator
with a finite density of particles interacting with a single mobile impurity—a
small quantum bath. We give perturbative arguments that support the stability
of localization in the strong interaction regime. Large-scale tensor network simulations
of dynamics are employed to corroborate the presence of the localized phase and
give quantitative predictions in the thermodynamic limit. We develop a phenomenological
description of the dynamics in the strong interaction regime, and we demonstrate
that the impurity effectively turns the Anderson insulator into an MBL phase,
giving rise to nontrivial entanglement dynamics well captured by our phenomenology.
acknowledged_ssus:
- _id: ScienComp
acknowledgement: We acknowledge useful discussions with M. Ljubotina. P. B., A. M.,
and M. S. were supported by the European Research Council (ERC) under the European
Union’s Horizon 2020 research and innovation program (Grant Agreement No. 850899).
D.A. was supported by the Swiss National Science Foundation and by the European
Research Council (ERC) under the European Union’s Horizon 2020 research and innovation
program (Grant Agreement No. 864597). The development of parallel TEBD code was
was supported by S. Elefante from the Scientific Computing (SciComp) that is part
of Scientific Service Units (SSU) of IST Austria. Some of the computations were
performed on the Baobab cluster of the University of Geneva.
article_number: L220203
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Pietro
full_name: Brighi, Pietro
id: 4115AF5C-F248-11E8-B48F-1D18A9856A87
last_name: Brighi
orcid: 0000-0002-7969-2729
- first_name: Alexios A.
full_name: Michailidis, Alexios A.
last_name: Michailidis
- first_name: Dmitry A.
full_name: Abanin, Dmitry A.
last_name: Abanin
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: Brighi P, Michailidis AA, Abanin DA, Serbyn M. Propagation of many-body localization
in an Anderson insulator. Physical Review B. 2022;105(22). doi:10.1103/physrevb.105.l220203
apa: Brighi, P., Michailidis, A. A., Abanin, D. A., & Serbyn, M. (2022). Propagation
of many-body localization in an Anderson insulator. Physical Review B.
American Physical Society. https://doi.org/10.1103/physrevb.105.l220203
chicago: Brighi, Pietro, Alexios A. Michailidis, Dmitry A. Abanin, and Maksym Serbyn.
“Propagation of Many-Body Localization in an Anderson Insulator.” Physical
Review B. American Physical Society, 2022. https://doi.org/10.1103/physrevb.105.l220203.
ieee: P. Brighi, A. A. Michailidis, D. A. Abanin, and M. Serbyn, “Propagation of
many-body localization in an Anderson insulator,” Physical Review B, vol.
105, no. 22. American Physical Society, 2022.
ista: Brighi P, Michailidis AA, Abanin DA, Serbyn M. 2022. Propagation of many-body
localization in an Anderson insulator. Physical Review B. 105(22), L220203.
mla: Brighi, Pietro, et al. “Propagation of Many-Body Localization in an Anderson
Insulator.” Physical Review B, vol. 105, no. 22, L220203, American Physical
Society, 2022, doi:10.1103/physrevb.105.l220203.
short: P. Brighi, A.A. Michailidis, D.A. Abanin, M. Serbyn, Physical Review B 105
(2022).
date_created: 2022-06-29T20:20:47Z
date_published: 2022-06-27T00:00:00Z
date_updated: 2023-08-03T07:23:52Z
day: '27'
department:
- _id: MaSe
doi: 10.1103/physrevb.105.l220203
ec_funded: 1
external_id:
arxiv:
- '2109.07332'
isi:
- '000823050000012'
intvolume: ' 105'
isi: 1
issue: '22'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: ' https://doi.org/10.48550/arXiv.2109.07332'
month: '06'
oa: 1
oa_version: Preprint
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review B
publication_identifier:
eissn:
- 2469-9969
issn:
- 2469-9950
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
related_material:
record:
- id: '12732'
relation: dissertation_contains
status: public
status: public
title: Propagation of many-body localization in an Anderson insulator
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 105
year: '2022'
...
---
_id: '11471'
abstract:
- lang: eng
text: 'Variational quantum algorithms are promising algorithms for achieving quantum
advantage on nearterm devices. The quantum hardware is used to implement a variational
wave function and measure observables, whereas the classical computer is used
to store and update the variational parameters. The optimization landscape of
expressive variational ansätze is however dominated by large regions in parameter
space, known as barren plateaus, with vanishing gradients, which prevents efficient
optimization. In this work we propose a general algorithm to avoid barren plateaus
in the initialization and throughout the optimization. To this end we define a
notion of weak barren plateaus (WBPs) based on the entropies of local reduced
density matrices. The presence of WBPs can be efficiently quantified using recently
introduced shadow tomography of the quantum state with a classical computer. We
demonstrate that avoidance of WBPs suffices to ensure sizable gradients in the
initialization. In addition, we demonstrate that decreasing the gradient step
size, guided by the entropies allows WBPs to be avoided during the optimization
process. This paves the way for efficient barren plateau-free optimization on
near-term devices. '
acknowledgement: "We thank Marco Cerezo, Zoe Holmes, and Nicholas Hunter-Jones for
fruitful discussion and valuable feedback. We also acknowledge Adam Smith, Johannes
Jakob Meyer, and Victor V. Albert for comments on the paper. The simulations were
performed in the Julia programming\r\nlanguage [65] using the Yao module [66]. S.H.S.,
R.A.M., A.A.M. and M.S. acknowledge support by the European Research Council (ERC)
under the European Union’s Horizon 2020 research and innovation program (Grant Agreement
No. 850899)."
article_number: '020365'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Stefan
full_name: Sack, Stefan
id: dd622248-f6e0-11ea-865d-ce382a1c81a5
last_name: Sack
orcid: 0000-0001-5400-8508
- first_name: Raimel A
full_name: Medina Ramos, Raimel A
id: CE680B90-D85A-11E9-B684-C920E6697425
last_name: Medina Ramos
orcid: 0000-0002-5383-2869
- first_name: Alexios
full_name: Michailidis, Alexios
id: 36EBAD38-F248-11E8-B48F-1D18A9856A87
last_name: Michailidis
orcid: 0000-0002-8443-1064
- first_name: Richard
full_name: Kueng, Richard
last_name: Kueng
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: Sack S, Medina Ramos RA, Michailidis A, Kueng R, Serbyn M. Avoiding barren
plateaus using classical shadows. PRX Quantum. 2022;3(2). doi:10.1103/prxquantum.3.020365
apa: Sack, S., Medina Ramos, R. A., Michailidis, A., Kueng, R., & Serbyn, M.
(2022). Avoiding barren plateaus using classical shadows. PRX Quantum.
American Physical Society. https://doi.org/10.1103/prxquantum.3.020365
chicago: Sack, Stefan, Raimel A Medina Ramos, Alexios Michailidis, Richard Kueng,
and Maksym Serbyn. “Avoiding Barren Plateaus Using Classical Shadows.” PRX
Quantum. American Physical Society, 2022. https://doi.org/10.1103/prxquantum.3.020365.
ieee: S. Sack, R. A. Medina Ramos, A. Michailidis, R. Kueng, and M. Serbyn, “Avoiding
barren plateaus using classical shadows,” PRX Quantum, vol. 3, no. 2. American
Physical Society, 2022.
ista: Sack S, Medina Ramos RA, Michailidis A, Kueng R, Serbyn M. 2022. Avoiding
barren plateaus using classical shadows. PRX Quantum. 3(2), 020365.
mla: Sack, Stefan, et al. “Avoiding Barren Plateaus Using Classical Shadows.” PRX
Quantum, vol. 3, no. 2, 020365, American Physical Society, 2022, doi:10.1103/prxquantum.3.020365.
short: S. Sack, R.A. Medina Ramos, A. Michailidis, R. Kueng, M. Serbyn, PRX Quantum
3 (2022).
date_created: 2022-06-29T20:21:32Z
date_published: 2022-06-29T00:00:00Z
date_updated: 2023-12-13T14:47:24Z
day: '29'
ddc:
- '530'
department:
- _id: MaSe
doi: 10.1103/prxquantum.3.020365
ec_funded: 1
external_id:
arxiv:
- '2201.08194'
isi:
- '000822564300001'
file:
- access_level: open_access
checksum: a7706b28d24a0e32a55ea04b82a2df43
content_type: application/pdf
creator: dernst
date_created: 2022-06-30T07:14:48Z
date_updated: 2022-06-30T07:14:48Z
file_id: '11472'
file_name: 2022_PRXQuantum_Sack.pdf
file_size: 4231591
relation: main_file
success: 1
file_date_updated: 2022-06-30T07:14:48Z
has_accepted_license: '1'
intvolume: ' 3'
isi: 1
issue: '2'
keyword:
- General Medicine
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: PRX Quantum
publication_identifier:
issn:
- 2691-3399
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
related_material:
record:
- id: '14622'
relation: dissertation_contains
status: public
status: public
title: Avoiding barren plateaus using classical shadows
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 3
year: '2022'
...
---
_id: '12269'
abstract:
- lang: eng
text: We study the thermalization of a small XX chain coupled to long, gapped XXZ
leads at either side by observing the relaxation dynamics of the whole system.
Using extensive tensor network simulations, we show that such systems, although
not integrable, appear to show either extremely slow thermalization or even lack
thereof since the two cannot be distinguished within the accuracy of our numerics.
We show that the persistent oscillations observed in the spin current in the middle
of the XX chain are related to eigenstates of the entire system located within
the gap of the boundary chains. We find from exact diagonalization that some of
these states remain strictly localized within the XX chain and do not hybridize
with the rest of the system. The frequencies of the persistent oscillations determined
by numerical simulations of dynamics match the energy differences between these
states exactly. This has important implications for open systems, where the strongly
interacting leads are often assumed to thermalize the central system. Our results
suggest that, if we employ gapped systems for the leads, this assumption does
not hold.
acknowledgement: "M.L. and T.P. acknowledge support from the European Research Council
(ERC) through the advanced grant 694544 – OMNES and the grant P1-0402 of Slovenian
Research Agency (ARRS). M.L. acknowledges support from the European Research Council
(ERC) through the starting grant 850899 – NEQuM. D.R. acknowledges support from
the Ministry of Electronics & Information Technology (MeitY), India under the grant
for “Centre for Excellence in Quantum\r\nTechnologies” with Ref. No. 4(7)/2020-ITEA. "
article_number: '054314'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Marko
full_name: Ljubotina, Marko
id: F75EE9BE-5C90-11EA-905D-16643DDC885E
last_name: Ljubotina
- first_name: Dibyendu
full_name: Roy, Dibyendu
last_name: Roy
- first_name: Tomaž
full_name: Prosen, Tomaž
last_name: Prosen
citation:
ama: Ljubotina M, Roy D, Prosen T. Absence of thermalization of free systems coupled
to gapped interacting reservoirs. Physical Review B. 2022;106(5). doi:10.1103/physrevb.106.054314
apa: Ljubotina, M., Roy, D., & Prosen, T. (2022). Absence of thermalization
of free systems coupled to gapped interacting reservoirs. Physical Review B.
American Physical Society. https://doi.org/10.1103/physrevb.106.054314
chicago: Ljubotina, Marko, Dibyendu Roy, and Tomaž Prosen. “Absence of Thermalization
of Free Systems Coupled to Gapped Interacting Reservoirs.” Physical Review
B. American Physical Society, 2022. https://doi.org/10.1103/physrevb.106.054314.
ieee: M. Ljubotina, D. Roy, and T. Prosen, “Absence of thermalization of free systems
coupled to gapped interacting reservoirs,” Physical Review B, vol. 106,
no. 5. American Physical Society, 2022.
ista: Ljubotina M, Roy D, Prosen T. 2022. Absence of thermalization of free systems
coupled to gapped interacting reservoirs. Physical Review B. 106(5), 054314.
mla: Ljubotina, Marko, et al. “Absence of Thermalization of Free Systems Coupled
to Gapped Interacting Reservoirs.” Physical Review B, vol. 106, no. 5,
054314, American Physical Society, 2022, doi:10.1103/physrevb.106.054314.
short: M. Ljubotina, D. Roy, T. Prosen, Physical Review B 106 (2022).
date_created: 2023-01-16T10:00:39Z
date_published: 2022-08-31T00:00:00Z
date_updated: 2023-08-04T10:07:33Z
day: '31'
department:
- _id: MaSe
doi: 10.1103/physrevb.106.054314
ec_funded: 1
external_id:
arxiv:
- '2106.08373'
isi:
- '000861332900005'
intvolume: ' 106'
isi: 1
issue: '5'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.48550/arXiv.2106.08373
month: '08'
oa: 1
oa_version: Preprint
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review B
publication_identifier:
eissn:
- 2469-9969
issn:
- 2469-9950
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Absence of thermalization of free systems coupled to gapped interacting reservoirs
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 106
year: '2022'
...
---
_id: '12276'
abstract:
- lang: eng
text: Ongoing development of quantum simulators allows for a progressively finer
degree of control of quantum many-body systems. This motivates the development
of efficient approaches to facilitate the control of such systems and enable the
preparation of nontrivial quantum states. Here we formulate an approach to control
quantum systems based on matrix product states (MPSs). We compare counterdiabatic
and leakage minimization approaches to the so-called local steering problem that
consists in finding the best value of the control parameters for generating a
unitary evolution of the specific MPS in a given direction. In order to benchmark
the different approaches, we apply them to the generalization of the PXP model
known to exhibit coherent quantum dynamics due to quantum many-body scars. We
find that the leakage-based approach generally outperforms the counterdiabatic
framework and use it to construct a Floquet model with quantum scars. We perform
the first steps towards global trajectory optimization and demonstrate entanglement
steering capabilities in the generalized PXP model. Finally, we apply our leakage
minimization approach to construct quantum scars in the periodically driven nonintegrable
Ising model.
acknowledgement: We thank A. A. Michailidis for insightful discussions. M.L. and M.S.
acknowledge support from the European Research Council (ERC) under the European
Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 850899).
D.A. is supported by the European Research Council (ERC) under the European Union’s
Horizon 2020 research and innovation programme (Grant Agreement No. 864597) and
by the Swiss National Science Foundation. The infinite TEBD simulations were performed
using the ITensor library [67].
article_number: '030343'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Marko
full_name: Ljubotina, Marko
id: F75EE9BE-5C90-11EA-905D-16643DDC885E
last_name: Ljubotina
- first_name: Barbara
full_name: Roos, Barbara
id: 5DA90512-D80F-11E9-8994-2E2EE6697425
last_name: Roos
orcid: 0000-0002-9071-5880
- first_name: Dmitry A.
full_name: Abanin, Dmitry A.
last_name: Abanin
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: Ljubotina M, Roos B, Abanin DA, Serbyn M. Optimal steering of matrix product
states and quantum many-body scars. PRX Quantum. 2022;3(3). doi:10.1103/prxquantum.3.030343
apa: Ljubotina, M., Roos, B., Abanin, D. A., & Serbyn, M. (2022). Optimal steering
of matrix product states and quantum many-body scars. PRX Quantum. American
Physical Society. https://doi.org/10.1103/prxquantum.3.030343
chicago: Ljubotina, Marko, Barbara Roos, Dmitry A. Abanin, and Maksym Serbyn. “Optimal
Steering of Matrix Product States and Quantum Many-Body Scars.” PRX Quantum.
American Physical Society, 2022. https://doi.org/10.1103/prxquantum.3.030343.
ieee: M. Ljubotina, B. Roos, D. A. Abanin, and M. Serbyn, “Optimal steering of matrix
product states and quantum many-body scars,” PRX Quantum, vol. 3, no. 3.
American Physical Society, 2022.
ista: Ljubotina M, Roos B, Abanin DA, Serbyn M. 2022. Optimal steering of matrix
product states and quantum many-body scars. PRX Quantum. 3(3), 030343.
mla: Ljubotina, Marko, et al. “Optimal Steering of Matrix Product States and Quantum
Many-Body Scars.” PRX Quantum, vol. 3, no. 3, 030343, American Physical
Society, 2022, doi:10.1103/prxquantum.3.030343.
short: M. Ljubotina, B. Roos, D.A. Abanin, M. Serbyn, PRX Quantum 3 (2022).
date_created: 2023-01-16T10:01:56Z
date_published: 2022-09-23T00:00:00Z
date_updated: 2023-01-30T11:05:23Z
day: '23'
ddc:
- '530'
department:
- _id: MaSe
- _id: RoSe
doi: 10.1103/prxquantum.3.030343
ec_funded: 1
external_id:
arxiv:
- '2204.02899'
file:
- access_level: open_access
checksum: ef8f0a1b5a019b3958009162de0fa4c3
content_type: application/pdf
creator: dernst
date_created: 2023-01-30T11:02:50Z
date_updated: 2023-01-30T11:02:50Z
file_id: '12457'
file_name: 2022_PRXQuantum_Ljubotina.pdf
file_size: 7661905
relation: main_file
success: 1
file_date_updated: 2023-01-30T11:02:50Z
has_accepted_license: '1'
intvolume: ' 3'
issue: '3'
keyword:
- General Medicine
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: PRX Quantum
publication_identifier:
eissn:
- 2691-3399
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Optimal steering of matrix product states and quantum many-body scars
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 3
year: '2022'
...
---
_id: '9048'
abstract:
- lang: eng
text: The analogy between an equilibrium partition function and the return probability
in many-body unitary dynamics has led to the concept of dynamical quantum phase
transition (DQPT). DQPTs are defined by nonanalyticities in the return amplitude
and are present in many models. In some cases, DQPTs can be related to equilibrium
concepts, such as order parameters, yet their universal description is an open
question. In this Letter, we provide first steps toward a classification of DQPTs
by using a matrix product state description of unitary dynamics in the thermodynamic
limit. This allows us to distinguish the two limiting cases of “precession” and
“entanglement” DQPTs, which are illustrated using an analytical description in
the quantum Ising model. While precession DQPTs are characterized by a large entanglement
gap and are semiclassical in their nature, entanglement DQPTs occur near avoided
crossings in the entanglement spectrum and can be distinguished by a complex pattern
of nonlocal correlations. We demonstrate the existence of precession and entanglement
DQPTs beyond Ising models, discuss observables that can distinguish them, and
relate their interplay to complex DQPT phenomenology.
acknowledgement: "S. D. N. acknowledges funding from the Institute of Science and
Technology (IST) Austria and from the European Union’s Horizon 2020 Research and
Innovation Programme under the Marie Skłodowska-Curie Grant Agreement No. 754411.
A. M. and M. S. were supported by the European Research Council (ERC) under the
European Union’s Horizon 2020 Research and\r\nInnovation Programme (Grant Agreement
No. 850899)."
article_number: '040602'
article_processing_charge: Yes
article_type: original
arxiv: 1
author:
- first_name: Stefano
full_name: De Nicola, Stefano
id: 42832B76-F248-11E8-B48F-1D18A9856A87
last_name: De Nicola
orcid: 0000-0002-4842-6671
- first_name: Alexios
full_name: Michailidis, Alexios
id: 36EBAD38-F248-11E8-B48F-1D18A9856A87
last_name: Michailidis
orcid: 0000-0002-8443-1064
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: De Nicola S, Michailidis A, Serbyn M. Entanglement view of dynamical quantum
phase transitions. Physical Review Letters. 2021;126(4). doi:10.1103/physrevlett.126.040602
apa: De Nicola, S., Michailidis, A., & Serbyn, M. (2021). Entanglement view
of dynamical quantum phase transitions. Physical Review Letters. American
Physical Society. https://doi.org/10.1103/physrevlett.126.040602
chicago: De Nicola, Stefano, Alexios Michailidis, and Maksym Serbyn. “Entanglement
View of Dynamical Quantum Phase Transitions.” Physical Review Letters.
American Physical Society, 2021. https://doi.org/10.1103/physrevlett.126.040602.
ieee: S. De Nicola, A. Michailidis, and M. Serbyn, “Entanglement view of dynamical
quantum phase transitions,” Physical Review Letters, vol. 126, no. 4. American
Physical Society, 2021.
ista: De Nicola S, Michailidis A, Serbyn M. 2021. Entanglement view of dynamical
quantum phase transitions. Physical Review Letters. 126(4), 040602.
mla: De Nicola, Stefano, et al. “Entanglement View of Dynamical Quantum Phase Transitions.”
Physical Review Letters, vol. 126, no. 4, 040602, American Physical Society,
2021, doi:10.1103/physrevlett.126.040602.
short: S. De Nicola, A. Michailidis, M. Serbyn, Physical Review Letters 126 (2021).
date_created: 2021-02-01T09:20:00Z
date_published: 2021-01-29T00:00:00Z
date_updated: 2023-09-05T12:08:58Z
day: '29'
ddc:
- '530'
department:
- _id: MaSe
doi: 10.1103/physrevlett.126.040602
ec_funded: 1
external_id:
arxiv:
- '2008.04894'
isi:
- '000613148200001'
file:
- access_level: open_access
checksum: d9acbc502390ed7a97e631d23ae19ecd
content_type: application/pdf
creator: dernst
date_created: 2021-02-03T12:47:04Z
date_updated: 2021-02-03T12:47:04Z
file_id: '9074'
file_name: 2021_PhysicalRevLett_DeNicola.pdf
file_size: 398075
relation: main_file
success: 1
file_date_updated: 2021-02-03T12:47:04Z
has_accepted_license: '1'
intvolume: ' 126'
isi: 1
issue: '4'
keyword:
- General Physics and Astronomy
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review Letters
publication_identifier:
eissn:
- 1079-7114
issn:
- 0031-9007
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: Entanglement view of dynamical quantum phase transitions
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 126
year: '2021'
...
---
_id: '9428'
abstract:
- lang: eng
text: Thermalization is the inevitable fate of many complex quantum systems, whose
dynamics allow them to fully explore the vast configuration space regardless of
the initial state---the behaviour known as quantum ergodicity. In a quest for
experimental realizations of coherent long-time dynamics, efforts have focused
on ergodicity-breaking mechanisms, such as integrability and localization. The
recent discovery of persistent revivals in quantum simulators based on Rydberg
atoms have pointed to the existence of a new type of behaviour where the system
rapidly relaxes for most initial conditions, while certain initial states give
rise to non-ergodic dynamics. This collective effect has been named ”quantum many-body
scarring’by analogy with a related form of weak ergodicity breaking that occurs
for a single particle inside a stadium billiard potential. In this Review, we
provide a pedagogical introduction to quantum many-body scars and highlight the
emerging connections with the semiclassical quantization of many-body systems.
We discuss the relation between scars and more general routes towards weak violations
of ergodicity due to embedded algebras and non-thermal eigenstates, and highlight
possible applications of scars in quantum technology.
acknowledgement: We thank our collaborators K. Bull, S. Choi, J.-Y. Desaules, W. W.
Ho, A. Hudomal, M. Lukin, I. Martin, H. Pichler, N. Regnault, I. Vasić and in particular
A. Michailidis and C. Turner, without whom this work would not have been possible.
We also benefited from discussions with E. Altman, B. A. Bernevig, A. Chandran,
P. Fendley, V. Khemani and L. Motrunich. M.S. was supported by the European Research
Council (ERC) under the European Union’s Horizon 2020 research and innovation programme
(grant agreement no. 850899). D.A.A. was supported by the Swiss National Science
Foundation and by the ERC under the European Union’s Horizon 2020 research and innovation
programme (grant agreement no. 864597). Z.P. acknowledges support by the Leverhulme
Trust Research Leadership Award RL-2019-015.
article_processing_charge: No
article_type: review
arxiv: 1
author:
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
- first_name: Dmitry A.
full_name: Abanin, Dmitry A.
last_name: Abanin
- first_name: Zlatko
full_name: Papić, Zlatko
last_name: Papić
citation:
ama: Serbyn M, Abanin DA, Papić Z. Quantum many-body scars and weak breaking of
ergodicity. Nature Physics. 2021;17(6):675–685. doi:10.1038/s41567-021-01230-2
apa: Serbyn, M., Abanin, D. A., & Papić, Z. (2021). Quantum many-body scars
and weak breaking of ergodicity. Nature Physics. Nature Research. https://doi.org/10.1038/s41567-021-01230-2
chicago: Serbyn, Maksym, Dmitry A. Abanin, and Zlatko Papić. “Quantum Many-Body
Scars and Weak Breaking of Ergodicity.” Nature Physics. Nature Research,
2021. https://doi.org/10.1038/s41567-021-01230-2.
ieee: M. Serbyn, D. A. Abanin, and Z. Papić, “Quantum many-body scars and weak breaking
of ergodicity,” Nature Physics, vol. 17, no. 6. Nature Research, pp. 675–685,
2021.
ista: Serbyn M, Abanin DA, Papić Z. 2021. Quantum many-body scars and weak breaking
of ergodicity. Nature Physics. 17(6), 675–685.
mla: Serbyn, Maksym, et al. “Quantum Many-Body Scars and Weak Breaking of Ergodicity.”
Nature Physics, vol. 17, no. 6, Nature Research, 2021, pp. 675–685, doi:10.1038/s41567-021-01230-2.
short: M. Serbyn, D.A. Abanin, Z. Papić, Nature Physics 17 (2021) 675–685.
date_created: 2021-05-28T09:03:50Z
date_published: 2021-06-01T00:00:00Z
date_updated: 2023-10-18T08:20:59Z
day: '01'
ddc:
- '539'
department:
- _id: MaSe
doi: 10.1038/s41567-021-01230-2
ec_funded: 1
external_id:
arxiv:
- '2011.09486'
isi:
- '000655563800002'
file:
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checksum: 316ed42ea1b42b0f1a3025bb476266fc
content_type: application/pdf
creator: patrickd
date_created: 2021-09-20T09:27:43Z
date_updated: 2021-12-02T23:30:03Z
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isi: 1
issue: '6'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Preprint
page: 675–685
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Nature Physics
publication_identifier:
eissn:
- 1745-2481
publication_status: published
publisher: Nature Research
quality_controlled: '1'
status: public
title: Quantum many-body scars and weak breaking of ergodicity
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 17
year: '2021'
...
---
_id: '9618'
abstract:
- lang: eng
text: The control of nonequilibrium quantum dynamics in many-body systems is challenging
because interactions typically lead to thermalization and a chaotic spreading
throughout Hilbert space. We investigate nonequilibrium dynamics after rapid quenches
in a many-body system composed of 3 to 200 strongly interacting qubits in one
and two spatial dimensions. Using a programmable quantum simulator based on Rydberg
atom arrays, we show that coherent revivals associated with so-called quantum
many-body scars can be stabilized by periodic driving, which generates a robust
subharmonic response akin to discrete time-crystalline order. We map Hilbert space
dynamics, geometry dependence, phase diagrams, and system-size dependence of this
emergent phenomenon, demonstrating new ways to steer complex dynamics in many-body
systems and enabling potential applications in quantum information science.
acknowledgement: 'We thank many members of the Harvard AMO community, particularly
E. Urbach, S. Dakoulas, and J. Doyle for their efforts enabling safe and productive
operation of our laboratories during 2020. We thank D. Abanin, I. Cong, F. Machado,
H. Pichler, N. Yao, B. Ye, and H. Zhou for stimulating discussions. Funding: We
acknowledge financial support from the Center for Ultracold Atoms, the National
Science Foundation, the Vannevar Bush Faculty Fellowship, the U.S. Department of
Energy (LBNL QSA Center and grant no. DE-SC0021013), the Office of Naval Research,
the Army Research Office MURI, the DARPA DRINQS program (grant no. D18AC00033),
and the DARPA ONISQ program (grant no. W911NF2010021). The authors acknowledge support
from the NSF Graduate Research Fellowship Program (grant DGE1745303) and The Fannie
and John Hertz Foundation (D.B.); a National Defense Science and Engineering Graduate
(NDSEG) fellowship (H.L.); a fellowship from the Max Planck/Harvard Research Center
for Quantum Optics (G.S.); Gordon College (T.T.W.); the European Research Council
(ERC) under the European Union’s Horizon 2020 research and innovation program (grant
agreement no. 850899) (A.A.M. and M.S.); a Department of Energy Computational Science
Graduate Fellowship under award number DE-SC0021110 (N.M.); the Moore Foundation’s
EPiQS Initiative grant no. GBMF4306, the NUS Development grant AY2019/2020, and
the Stanford Institute of Theoretical Physics (W.W.H.); and the Miller Institute
for Basic Research in Science (S.C.). Author contributions: D.B., A.O., H.L., A.K.,
G.S., S.E., and T.T.W. contributed to the building of the experimental setup, performed
the measurements, and analyzed the data. A.A.M., N.M., W.W.H., S.C., and M.S. performed
theoretical analysis. All work was supervised by M.G., V.V., and M.D.L. All authors
discussed the results and contributed to the manuscript. Competing interests: M.G.,
V.V., and M.D.L. are co-founders and shareholders of QuEra Computing. A.O. is a
shareholder of QuEra Computing. Data and materials availability: All data needed
to evaluate the conclusions in the paper are present in the paper and the supplementary
materials.'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: D.
full_name: Bluvstein, D.
last_name: Bluvstein
- first_name: A.
full_name: Omran, A.
last_name: Omran
- first_name: H.
full_name: Levine, H.
last_name: Levine
- first_name: A.
full_name: Keesling, A.
last_name: Keesling
- first_name: G.
full_name: Semeghini, G.
last_name: Semeghini
- first_name: S.
full_name: Ebadi, S.
last_name: Ebadi
- first_name: T. T.
full_name: Wang, T. T.
last_name: Wang
- first_name: Alexios
full_name: Michailidis, Alexios
id: 36EBAD38-F248-11E8-B48F-1D18A9856A87
last_name: Michailidis
orcid: 0000-0002-8443-1064
- first_name: N.
full_name: Maskara, N.
last_name: Maskara
- first_name: W. W.
full_name: Ho, W. W.
last_name: Ho
- first_name: S.
full_name: Choi, S.
last_name: Choi
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
- first_name: M.
full_name: Greiner, M.
last_name: Greiner
- first_name: V.
full_name: Vuletić, V.
last_name: Vuletić
- first_name: M. D.
full_name: Lukin, M. D.
last_name: Lukin
citation:
ama: Bluvstein D, Omran A, Levine H, et al. Controlling quantum many-body dynamics
in driven Rydberg atom arrays. Science. 2021;371(6536):1355-1359. doi:10.1126/science.abg2530
apa: Bluvstein, D., Omran, A., Levine, H., Keesling, A., Semeghini, G., Ebadi, S.,
… Lukin, M. D. (2021). Controlling quantum many-body dynamics in driven Rydberg
atom arrays. Science. AAAS. https://doi.org/10.1126/science.abg2530
chicago: Bluvstein, D., A. Omran, H. Levine, A. Keesling, G. Semeghini, S. Ebadi,
T. T. Wang, et al. “Controlling Quantum Many-Body Dynamics in Driven Rydberg Atom
Arrays.” Science. AAAS, 2021. https://doi.org/10.1126/science.abg2530.
ieee: D. Bluvstein et al., “Controlling quantum many-body dynamics in driven
Rydberg atom arrays,” Science, vol. 371, no. 6536. AAAS, pp. 1355–1359,
2021.
ista: Bluvstein D, Omran A, Levine H, Keesling A, Semeghini G, Ebadi S, Wang TT,
Michailidis A, Maskara N, Ho WW, Choi S, Serbyn M, Greiner M, Vuletić V, Lukin
MD. 2021. Controlling quantum many-body dynamics in driven Rydberg atom arrays.
Science. 371(6536), 1355–1359.
mla: Bluvstein, D., et al. “Controlling Quantum Many-Body Dynamics in Driven Rydberg
Atom Arrays.” Science, vol. 371, no. 6536, AAAS, 2021, pp. 1355–59, doi:10.1126/science.abg2530.
short: D. Bluvstein, A. Omran, H. Levine, A. Keesling, G. Semeghini, S. Ebadi, T.T.
Wang, A. Michailidis, N. Maskara, W.W. Ho, S. Choi, M. Serbyn, M. Greiner, V.
Vuletić, M.D. Lukin, Science 371 (2021) 1355–1359.
date_created: 2021-06-29T12:04:05Z
date_published: 2021-03-26T00:00:00Z
date_updated: 2023-08-10T13:57:07Z
day: '26'
ddc:
- '539'
department:
- _id: MaSe
doi: 10.1126/science.abg2530
ec_funded: 1
external_id:
arxiv:
- '2012.12276'
isi:
- '000636043400048'
pmid:
- '33632894'
file:
- access_level: open_access
checksum: 0b356fd10ab9bb95177d4c047d4e9c1a
content_type: application/pdf
creator: patrickd
date_created: 2021-09-23T14:00:05Z
date_updated: 2021-09-23T14:00:05Z
file_id: '10040'
file_name: scars_subharmonic_combined_manuscript_2_11_2021 (2)-1.pdf
file_size: 3671159
relation: main_file
success: 1
file_date_updated: 2021-09-23T14:00:05Z
has_accepted_license: '1'
intvolume: ' 371'
isi: 1
issue: '6536'
keyword:
- Multidisciplinary
language:
- iso: eng
month: '03'
oa: 1
oa_version: Preprint
page: 1355-1359
pmid: 1
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Science
publication_identifier:
eissn:
- 1095-9203
issn:
- 0036-8075
publication_status: published
publisher: AAAS
quality_controlled: '1'
scopus_import: '1'
status: public
title: Controlling quantum many-body dynamics in driven Rydberg atom arrays
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 371
year: '2021'
...
---
_id: '10067'
abstract:
- lang: eng
text: The search for novel entangled phases of matter has lead to the recent discovery
of a new class of “entanglement transitions,” exemplified by random tensor networks
and monitored quantum circuits. Most known examples can be understood as some
classical ordering transitions in an underlying statistical mechanics model, where
entanglement maps onto the free-energy cost of inserting a domain wall. In this
paper we study the possibility of entanglement transitions driven by physics beyond
such statistical mechanics mappings. Motivated by recent applications of neural-network-inspired
variational Ansätze, we investigate under what conditions on the variational parameters
these Ansätze can capture an entanglement transition. We study the entanglement
scaling of short-range restricted Boltzmann machine (RBM) quantum states with
random phases. For uncorrelated random phases, we analytically demonstrate the
absence of an entanglement transition and reveal subtle finite-size effects in
finite-size numerical simulations. Introducing phases with correlations decaying
as 1/r^α in real space, we observe three regions with a different scaling of entanglement
entropy depending on the exponent α. We study the nature of the transition between
these regions, finding numerical evidence for critical behavior. Our work establishes
the presence of long-range correlated phases in RBM-based wave functions as a
required ingredient for entanglement transitions.
acknowledgement: We would like to thank S. De Nicola, P. Brighi, and V. Karle for
fruitful discussions and valuable feedback on the manuscript. R.M. and M.S. acknowledge
support by the European Research Council (ERC) under the European Union's Horizon
2020 research and innovation program (Grant Agreement No. 850899). R.V. acknowledges
support from the US Department of Energy, Office of Science, Basic Energy Sciences,
under Early Career Award No. DE-SC0019168, and the Alfred P. Sloan Foundation through
a Sloan Research Fellowship.
article_number: '104205'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Raimel A
full_name: Medina Ramos, Raimel A
id: CE680B90-D85A-11E9-B684-C920E6697425
last_name: Medina Ramos
orcid: 0000-0002-5383-2869
- first_name: Romain
full_name: Vasseur, Romain
last_name: Vasseur
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: Medina Ramos RA, Vasseur R, Serbyn M. Entanglement transitions from restricted
Boltzmann machines. Physical Review B. 2021;104(10). doi:10.1103/physrevb.104.104205
apa: Medina Ramos, R. A., Vasseur, R., & Serbyn, M. (2021). Entanglement transitions
from restricted Boltzmann machines. Physical Review B. American Physical
Society. https://doi.org/10.1103/physrevb.104.104205
chicago: Medina Ramos, Raimel A, Romain Vasseur, and Maksym Serbyn. “Entanglement
Transitions from Restricted Boltzmann Machines.” Physical Review B. American
Physical Society, 2021. https://doi.org/10.1103/physrevb.104.104205.
ieee: R. A. Medina Ramos, R. Vasseur, and M. Serbyn, “Entanglement transitions from
restricted Boltzmann machines,” Physical Review B, vol. 104, no. 10. American
Physical Society, 2021.
ista: Medina Ramos RA, Vasseur R, Serbyn M. 2021. Entanglement transitions from
restricted Boltzmann machines. Physical Review B. 104(10), 104205.
mla: Medina Ramos, Raimel A., et al. “Entanglement Transitions from Restricted Boltzmann
Machines.” Physical Review B, vol. 104, no. 10, 104205, American Physical
Society, 2021, doi:10.1103/physrevb.104.104205.
short: R.A. Medina Ramos, R. Vasseur, M. Serbyn, Physical Review B 104 (2021).
date_created: 2021-10-02T09:03:42Z
date_published: 2021-09-30T00:00:00Z
date_updated: 2023-08-14T07:24:47Z
day: '30'
department:
- _id: MaSe
doi: 10.1103/physrevb.104.104205
ec_funded: 1
external_id:
arxiv:
- '2107.05735'
isi:
- '000704414400002'
intvolume: ' 104'
isi: 1
issue: '10'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2107.05735
month: '09'
oa: 1
oa_version: Preprint
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review B
publication_identifier:
eissn:
- 2469-9969
issn:
- 2469-9950
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: Entanglement transitions from restricted Boltzmann machines
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 104
year: '2021'
...
---
_id: '10545'
abstract:
- lang: eng
text: Classical models with complex energy landscapes represent a perspective avenue
for the near-term application of quantum simulators. Until now, many theoretical
works studied the performance of quantum algorithms for models with a unique ground
state. However, when the classical problem is in a so-called clustering phase,
the ground state manifold is highly degenerate. As an example, we consider a 3-XORSAT
model defined on simple hypergraphs. The degeneracy of classical ground state
manifold translates into the emergence of an extensive number of Z2 symmetries,
which remain intact even in the presence of a quantum transverse magnetic field.
We establish a general duality approach that restricts the quantum problem to
a given sector of conserved Z2 charges and use it to study how the outcome of
the quantum adiabatic algorithm depends on the hypergraph geometry. We show that
the tree hypergraph which corresponds to a classically solvable instance of the
3-XORSAT problem features a constant gap, whereas the closed hypergraph encounters
a second-order phase transition with a gap vanishing as a power-law in the problem
size. The duality developed in this work provides a practical tool for studies
of quantum models with classically degenerate energy manifold and reveals potential
connections between glasses and gauge theories.
acknowledgement: We would like to thank S. De Nicola, A. Michaidilis, T. Gulden, Y.
Nez-Fernndez, P. Brighi, and S. Sack for fruitful discussions and valuable feedback
on the manuscript. M.S. acknowledges useful discussions with E. Altman, L. Cugliandolo,
and C. Laumann. We acknowledge support from the European Research Council (ERC)
under the European Union's Horizon 2020 Research and Innovation Programme Grant
Agreement No. 850899.
article_number: '062423'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Raimel A
full_name: Medina Ramos, Raimel A
id: CE680B90-D85A-11E9-B684-C920E6697425
last_name: Medina Ramos
orcid: 0000-0002-5383-2869
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: Medina Ramos RA, Serbyn M. Duality approach to quantum annealing of the 3-variable
exclusive-or satisfiability problem (3-XORSAT). Physical Review A. 2021;104(6).
doi:10.1103/physreva.104.062423
apa: Medina Ramos, R. A., & Serbyn, M. (2021). Duality approach to quantum annealing
of the 3-variable exclusive-or satisfiability problem (3-XORSAT). Physical
Review A. American Physical Society. https://doi.org/10.1103/physreva.104.062423
chicago: Medina Ramos, Raimel A, and Maksym Serbyn. “Duality Approach to Quantum
Annealing of the 3-Variable Exclusive-or Satisfiability Problem (3-XORSAT).” Physical
Review A. American Physical Society, 2021. https://doi.org/10.1103/physreva.104.062423.
ieee: R. A. Medina Ramos and M. Serbyn, “Duality approach to quantum annealing of
the 3-variable exclusive-or satisfiability problem (3-XORSAT),” Physical Review
A, vol. 104, no. 6. American Physical Society, 2021.
ista: Medina Ramos RA, Serbyn M. 2021. Duality approach to quantum annealing of
the 3-variable exclusive-or satisfiability problem (3-XORSAT). Physical Review
A. 104(6), 062423.
mla: Medina Ramos, Raimel A., and Maksym Serbyn. “Duality Approach to Quantum Annealing
of the 3-Variable Exclusive-or Satisfiability Problem (3-XORSAT).” Physical
Review A, vol. 104, no. 6, 062423, American Physical Society, 2021, doi:10.1103/physreva.104.062423.
short: R.A. Medina Ramos, M. Serbyn, Physical Review A 104 (2021).
date_created: 2021-12-14T20:46:07Z
date_published: 2021-12-14T00:00:00Z
date_updated: 2023-08-17T06:22:49Z
day: '14'
department:
- _id: MaSe
doi: 10.1103/physreva.104.062423
ec_funded: 1
external_id:
arxiv:
- '2106.06344'
isi:
- '000753659200004'
intvolume: ' 104'
isi: 1
issue: '6'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2106.06344
month: '12'
oa: 1
oa_version: Preprint
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review A
publication_identifier:
eissn:
- 2469-9934
issn:
- 2469-9926
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: Duality approach to quantum annealing of the 3-variable exclusive-or satisfiability
problem (3-XORSAT)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 104
year: '2021'
...
---
_id: '9760'
abstract:
- lang: eng
text: "The quantum approximate optimization algorithm (QAOA) is a prospective near-term
quantum algorithm due to its modest circuit depth and promising benchmarks. However,
an external parameter optimization required in the QAOA could become a performance
bottleneck. This motivates studies of the optimization landscape and search for
heuristic ways of parameter initialization. In this work we visualize the optimization
landscape of the QAOA applied to the MaxCut problem on random graphs, demonstrating
that random initialization of the QAOA is prone to converging to local minima
with suboptimal performance. We introduce the initialization of QAOA parameters
based on the Trotterized quantum annealing (TQA) protocol, parameterized by the
Trotter time step. We find that the TQA initialization allows to circumvent\r\nthe
issue of false minima for a broad range of time steps, yielding the same performance
as the best result out of an exponentially scaling number of random initializations.
Moreover, we demonstrate that the optimal value of the time step coincides with
the point of proliferation of Trotter errors in quantum annealing. Our results
suggest practical ways of initializing QAOA protocols on near-term quantum devices
and reveal new connections between QAOA and quantum annealing."
acknowledgement: We would like to thank D. Abanin and R. Medina for fruitful discussions
and A. Smith and I. Kim for valuable feedback on the manuscript. We acknowledge
support by the European Research Council (ERC) under the European Union’s Horizon
2020 research and innovation program (Grant Agreement No. 850899).
article_number: '491'
article_processing_charge: Yes
article_type: original
arxiv: 1
author:
- first_name: Stefan
full_name: Sack, Stefan
id: dd622248-f6e0-11ea-865d-ce382a1c81a5
last_name: Sack
orcid: 0000-0001-5400-8508
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: Sack S, Serbyn M. Quantum annealing initialization of the quantum approximate
optimization algorithm. Quantum. 2021;5. doi:10.22331/Q-2021-07-01-491
apa: Sack, S., & Serbyn, M. (2021). Quantum annealing initialization of the
quantum approximate optimization algorithm. Quantum. Verein zur Förderung
des Open Access Publizierens in den Quantenwissenschaften. https://doi.org/10.22331/Q-2021-07-01-491
chicago: Sack, Stefan, and Maksym Serbyn. “Quantum Annealing Initialization of the
Quantum Approximate Optimization Algorithm.” Quantum. Verein zur Förderung
des Open Access Publizierens in den Quantenwissenschaften, 2021. https://doi.org/10.22331/Q-2021-07-01-491.
ieee: S. Sack and M. Serbyn, “Quantum annealing initialization of the quantum approximate
optimization algorithm,” Quantum, vol. 5. Verein zur Förderung des Open
Access Publizierens in den Quantenwissenschaften, 2021.
ista: Sack S, Serbyn M. 2021. Quantum annealing initialization of the quantum approximate
optimization algorithm. Quantum. 5, 491.
mla: Sack, Stefan, and Maksym Serbyn. “Quantum Annealing Initialization of the Quantum
Approximate Optimization Algorithm.” Quantum, vol. 5, 491, Verein zur Förderung
des Open Access Publizierens in den Quantenwissenschaften, 2021, doi:10.22331/Q-2021-07-01-491.
short: S. Sack, M. Serbyn, Quantum 5 (2021).
date_created: 2021-08-01T22:01:21Z
date_published: 2021-07-01T00:00:00Z
date_updated: 2023-12-13T14:47:25Z
day: '01'
ddc:
- '530'
department:
- _id: GradSch
- _id: MaSe
doi: 10.22331/Q-2021-07-01-491
ec_funded: 1
external_id:
arxiv:
- '2101.05742'
isi:
- '000669830600001'
file:
- access_level: open_access
checksum: 9706c2bb8e748e9b5b138381995a7f6f
content_type: application/pdf
creator: cchlebak
date_created: 2021-08-06T06:44:31Z
date_updated: 2021-08-06T06:44:31Z
file_id: '9774'
file_name: 2021_Quantum_Sack.pdf
file_size: 2312482
relation: main_file
file_date_updated: 2021-08-06T06:44:31Z
has_accepted_license: '1'
intvolume: ' 5'
isi: 1
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Quantum
publication_identifier:
eissn:
- 2521-327X
publication_status: published
publisher: Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften
quality_controlled: '1'
related_material:
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relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Quantum annealing initialization of the quantum approximate optimization algorithm
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 5
year: '2021'
...
---
_id: '9903'
abstract:
- lang: eng
text: Eigenstate thermalization in quantum many-body systems implies that eigenstates
at high energy are similar to random vectors. Identifying systems where at least
some eigenstates are nonthermal is an outstanding question. In this Letter we
show that interacting quantum models that have a nullspace—a degenerate subspace
of eigenstates at zero energy (zero modes), which corresponds to infinite temperature,
provide a route to nonthermal eigenstates. We analytically show the existence
of a zero mode which can be represented as a matrix product state for a certain
class of local Hamiltonians. In the more general case we use a subspace disentangling
algorithm to generate an orthogonal basis of zero modes characterized by increasing
entanglement entropy. We show evidence for an area-law entanglement scaling of
the least-entangled zero mode in the broad parameter regime, leading to a conjecture
that all local Hamiltonians with the nullspace feature zero modes with area-law
entanglement scaling and, as such, break the strong thermalization hypothesis.
Finally, we find zero modes in constrained models and propose a setup for observing
their experimental signatures.
acknowledgement: "We acknowledge useful discussions with V. Gritsev and A. Garkun
and suggestions on implementation of the\r\nPPXPP model by D. Bluvstein. A. M. and
M. S. were supported by the European Research Council (ERC) under\r\nthe European
Union’s Horizon 2020 research and innovation program (Grant Agreement No. 850899)"
article_number: '060602'
article_processing_charge: Yes (in subscription journal)
article_type: letter_note
arxiv: 1
author:
- first_name: Volker
full_name: Karle, Volker
id: D7C012AE-D7ED-11E9-95E8-1EC5E5697425
last_name: Karle
orcid: 0000-0002-6963-0129
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
- first_name: Alexios
full_name: Michailidis, Alexios
id: 36EBAD38-F248-11E8-B48F-1D18A9856A87
last_name: Michailidis
orcid: 0000-0002-8443-1064
citation:
ama: Karle V, Serbyn M, Michailidis A. Area-law entangled eigenstates from nullspaces
of local Hamiltonians. Physical Review Letters. 2021;127(6). doi:10.1103/physrevlett.127.060602
apa: Karle, V., Serbyn, M., & Michailidis, A. (2021). Area-law entangled eigenstates
from nullspaces of local Hamiltonians. Physical Review Letters. American
Physical Society. https://doi.org/10.1103/physrevlett.127.060602
chicago: Karle, Volker, Maksym Serbyn, and Alexios Michailidis. “Area-Law Entangled
Eigenstates from Nullspaces of Local Hamiltonians.” Physical Review Letters.
American Physical Society, 2021. https://doi.org/10.1103/physrevlett.127.060602.
ieee: V. Karle, M. Serbyn, and A. Michailidis, “Area-law entangled eigenstates from
nullspaces of local Hamiltonians,” Physical Review Letters, vol. 127, no.
6. American Physical Society, 2021.
ista: Karle V, Serbyn M, Michailidis A. 2021. Area-law entangled eigenstates from
nullspaces of local Hamiltonians. Physical Review Letters. 127(6), 060602.
mla: Karle, Volker, et al. “Area-Law Entangled Eigenstates from Nullspaces of Local
Hamiltonians.” Physical Review Letters, vol. 127, no. 6, 060602, American
Physical Society, 2021, doi:10.1103/physrevlett.127.060602.
short: V. Karle, M. Serbyn, A. Michailidis, Physical Review Letters 127 (2021).
date_created: 2021-08-13T09:27:39Z
date_published: 2021-08-06T00:00:00Z
date_updated: 2023-08-11T10:43:27Z
day: '06'
ddc:
- '539'
department:
- _id: MaSe
- _id: GradSch
- _id: MiLe
doi: 10.1103/physrevlett.127.060602
ec_funded: 1
external_id:
arxiv:
- '2102.13633'
isi:
- '000684276000002'
file:
- access_level: open_access
checksum: 51218f302dcef99d90d1209809fcc874
content_type: application/pdf
creator: mserbyn
date_created: 2021-08-13T09:28:08Z
date_updated: 2021-08-13T09:28:08Z
file_id: '9904'
file_name: PhysRevLett.127.060602_SOM.pdf
file_size: 5064231
relation: main_file
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file_date_updated: 2021-08-13T09:28:08Z
has_accepted_license: '1'
intvolume: ' 127'
isi: 1
issue: '6'
language:
- iso: eng
month: '08'
oa: 1
oa_version: Published Version
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review Letters
publication_identifier:
eissn:
- 1079-7114
issn:
- 0031-9007
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: Area-law entangled eigenstates from nullspaces of local Hamiltonians
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 127
year: '2021'
...
---
_id: '9960'
abstract:
- lang: eng
text: The control of many-body quantum dynamics in complex systems is a key challenge
in the quest to reliably produce and manipulate large-scale quantum entangled
states. Recently, quench experiments in Rydberg atom arrays [Bluvstein et al.
Science 371, 1355 (2021)] demonstrated that coherent revivals associated with
quantum many-body scars can be stabilized by periodic driving, generating stable
subharmonic responses over a wide parameter regime. We analyze a simple, related
model where these phenomena originate from spatiotemporal ordering in an effective
Floquet unitary, corresponding to discrete time-crystalline behavior in a prethermal
regime. Unlike conventional discrete time crystals, the subharmonic response exists
only for Néel-like initial states, associated with quantum scars. We predict robustness
to perturbations and identify emergent timescales that could be observed in future
experiments. Our results suggest a route to controlling entanglement in interacting
quantum systems by combining periodic driving with many-body scars.
acknowledgement: We thank Dmitry Abanin, Ehud Altman, Iris Cong, Sepehr Ebadi, Alex
Keesling, Harry Levine, Ahmed Omran, Hannes Pichler, Rhine Samajdar, Guilia Semeghini,
Tout Wang, Norman Yao, and Harry Zhou or stimulating discussions. We acknowledge
support from the Center for Ultracold Atoms, the National Science Foundation, the
Vannevar Bush Faculty Fellowship, the U.S. Department of Energy, the Army Research
Office MURI, and the DARPA ONISQ program (M. L., N. M, W. W. H., D. B.); the European
Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation
Programme Grant Agreement No. 850899 (A. M. and M. S.); the Department of Energy
Computational Science Graduate Fellowship under Awards No. DESC0021110 (N. M.);
the Moore Foundation EPiQS initiative Grant No. GBMF4306, the National University
of Singapore (NUS) Development Grant AY2019/2020 and the Stanford Institute for
Theoretical Physics (W. W. H.); the NSF Graduate Research Fellowship Program (Grant
No. DGE1745303) and The Fannie and John Hertz Foundation (D. B.); the Miller Institute
for Basic Research in Science (S. C.); DOE Quantum Systems Accelerator – Contract
No. 7568717; and DOE Programmable Quantum Simulators for Lattice Gauge Theories
and Gauge-Gravity Correspondence – Grant No. DE-SC0021013.
article_number: '090602'
article_processing_charge: No
article_type: letter_note
arxiv: 1
author:
- first_name: N.
full_name: Maskara, N.
last_name: Maskara
- first_name: Alexios
full_name: Michailidis, Alexios
id: 36EBAD38-F248-11E8-B48F-1D18A9856A87
last_name: Michailidis
orcid: 0000-0002-8443-1064
- first_name: W. W.
full_name: Ho, W. W.
last_name: Ho
- first_name: D.
full_name: Bluvstein, D.
last_name: Bluvstein
- first_name: S.
full_name: Choi, S.
last_name: Choi
- first_name: M. D.
full_name: Lukin, M. D.
last_name: Lukin
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
citation:
ama: 'Maskara N, Michailidis A, Ho WW, et al. Discrete time-crystalline order enabled
by quantum many-body scars: Entanglement steering via periodic driving. Physical
Review Letters. 2021;127(9). doi:10.1103/PhysRevLett.127.090602'
apa: 'Maskara, N., Michailidis, A., Ho, W. W., Bluvstein, D., Choi, S., Lukin, M.
D., & Serbyn, M. (2021). Discrete time-crystalline order enabled by quantum
many-body scars: Entanglement steering via periodic driving. Physical Review
Letters. American Physical Society. https://doi.org/10.1103/PhysRevLett.127.090602'
chicago: 'Maskara, N., Alexios Michailidis, W. W. Ho, D. Bluvstein, S. Choi, M.
D. Lukin, and Maksym Serbyn. “Discrete Time-Crystalline Order Enabled by Quantum
Many-Body Scars: Entanglement Steering via Periodic Driving.” Physical Review
Letters. American Physical Society, 2021. https://doi.org/10.1103/PhysRevLett.127.090602.'
ieee: 'N. Maskara et al., “Discrete time-crystalline order enabled by quantum
many-body scars: Entanglement steering via periodic driving,” Physical Review
Letters, vol. 127, no. 9. American Physical Society, 2021.'
ista: 'Maskara N, Michailidis A, Ho WW, Bluvstein D, Choi S, Lukin MD, Serbyn M.
2021. Discrete time-crystalline order enabled by quantum many-body scars: Entanglement
steering via periodic driving. Physical Review Letters. 127(9), 090602.'
mla: 'Maskara, N., et al. “Discrete Time-Crystalline Order Enabled by Quantum Many-Body
Scars: Entanglement Steering via Periodic Driving.” Physical Review Letters,
vol. 127, no. 9, 090602, American Physical Society, 2021, doi:10.1103/PhysRevLett.127.090602.'
short: N. Maskara, A. Michailidis, W.W. Ho, D. Bluvstein, S. Choi, M.D. Lukin, M.
Serbyn, Physical Review Letters 127 (2021).
date_created: 2021-08-28T08:08:58Z
date_published: 2021-08-27T00:00:00Z
date_updated: 2023-08-11T10:57:51Z
day: '27'
department:
- _id: MaSe
doi: 10.1103/PhysRevLett.127.090602
ec_funded: 1
external_id:
arxiv:
- '2102.13160'
isi:
- '000692200100002'
intvolume: ' 127'
isi: 1
issue: '9'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2102.13160
month: '08'
oa: 1
oa_version: Submitted Version
project:
- _id: 23841C26-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '850899'
name: 'Non-Ergodic Quantum Matter: Universality, Dynamics and Control'
publication: Physical Review Letters
publication_identifier:
eissn:
- 1079-7114
issn:
- 0031-9007
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: 'Discrete time-crystalline order enabled by quantum many-body scars: Entanglement
steering via periodic driving'
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 127
year: '2021'
...