---
_id: '14517'
abstract:
- lang: eng
text: 'State-of-the-art transmon qubits rely on large capacitors, which systematically
improve their coherence due to reduced surface-loss participation. However, this
approach increases both the footprint and the parasitic cross-coupling and is
ultimately limited by radiation losses—a potential roadblock for scaling up quantum
processors to millions of qubits. In this work we present transmon qubits with
sizes as low as 36 × 39 µm2 with 100-nm-wide vacuum-gap capacitors that are micromachined
from commercial silicon-on-insulator wafers and shadow evaporated with aluminum.
We achieve a vacuum participation ratio up to 99.6% in an in-plane design that
is compatible with standard coplanar circuits. Qubit relaxationtime measurements
for small gaps with high zero-point electric field variance of up to 22 V/m reveal
a double exponential decay indicating comparably strong qubit interaction with
long-lived two-level systems. The exceptionally high selectivity of up to 20 dB
to the superconductor-vacuum interface allows us to precisely back out the sub-single-photon
dielectric loss tangent of aluminum oxide previously exposed to ambient conditions.
In terms of future scaling potential, we achieve a ratio of qubit quality factor
to a footprint area equal to 20 µm−2, which is comparable with the highest T1
devices relying on larger geometries, a value that could improve substantially
for lower surface-loss superconductors. '
acknowledged_ssus:
- _id: NanoFab
acknowledgement: "This work was supported by the Austrian Science Fund (FWF) through
BeyondC (F7105), the European Research Council under Grant Agreement No. 758053
(ERC StG QUNNECT) and a NOMIS foundation research grant. M.Z. was the recipient
of a SAIA scholarship, E.R. of\r\na DOC fellowship of the Austrian Academy of Sciences,
and M.P. of a Pöttinger scholarship at IST Austria. S.B. acknowledges support from
Marie Skłodowska Curie Program No. 707438 (MSC-IF SUPEREOM). J.M.F. acknowledges
support from the Horizon Europe Program HORIZON-CL4-2022-QUANTUM-01-SGA via Project
No. 101113946 OpenSuperQPlus100 and the ISTA Nanofabrication Facility."
article_number: '044054'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Martin
full_name: Zemlicka, Martin
id: 2DCF8DE6-F248-11E8-B48F-1D18A9856A87
last_name: Zemlicka
- first_name: Elena
full_name: Redchenko, Elena
id: 2C21D6E8-F248-11E8-B48F-1D18A9856A87
last_name: Redchenko
- first_name: Matilda
full_name: Peruzzo, Matilda
id: 3F920B30-F248-11E8-B48F-1D18A9856A87
last_name: Peruzzo
orcid: 0000-0002-3415-4628
- first_name: Farid
full_name: Hassani, Farid
id: 2AED110C-F248-11E8-B48F-1D18A9856A87
last_name: Hassani
orcid: 0000-0001-6937-5773
- first_name: Andrea
full_name: Trioni, Andrea
id: 42F71B44-F248-11E8-B48F-1D18A9856A87
last_name: Trioni
- first_name: Shabir
full_name: Barzanjeh, Shabir
id: 2D25E1F6-F248-11E8-B48F-1D18A9856A87
last_name: Barzanjeh
orcid: 0000-0003-0415-1423
- first_name: Johannes M
full_name: Fink, Johannes M
id: 4B591CBA-F248-11E8-B48F-1D18A9856A87
last_name: Fink
orcid: 0000-0001-8112-028X
citation:
ama: 'Zemlicka M, Redchenko E, Peruzzo M, et al. Compact vacuum-gap transmon qubits:
Selective and sensitive probes for superconductor surface losses. Physical
Review Applied. 2023;20(4). doi:10.1103/PhysRevApplied.20.044054'
apa: 'Zemlicka, M., Redchenko, E., Peruzzo, M., Hassani, F., Trioni, A., Barzanjeh,
S., & Fink, J. M. (2023). Compact vacuum-gap transmon qubits: Selective and
sensitive probes for superconductor surface losses. Physical Review Applied.
American Physical Society. https://doi.org/10.1103/PhysRevApplied.20.044054'
chicago: 'Zemlicka, Martin, Elena Redchenko, Matilda Peruzzo, Farid Hassani, Andrea
Trioni, Shabir Barzanjeh, and Johannes M Fink. “Compact Vacuum-Gap Transmon Qubits:
Selective and Sensitive Probes for Superconductor Surface Losses.” Physical
Review Applied. American Physical Society, 2023. https://doi.org/10.1103/PhysRevApplied.20.044054.'
ieee: 'M. Zemlicka et al., “Compact vacuum-gap transmon qubits: Selective
and sensitive probes for superconductor surface losses,” Physical Review Applied,
vol. 20, no. 4. American Physical Society, 2023.'
ista: 'Zemlicka M, Redchenko E, Peruzzo M, Hassani F, Trioni A, Barzanjeh S, Fink
JM. 2023. Compact vacuum-gap transmon qubits: Selective and sensitive probes for
superconductor surface losses. Physical Review Applied. 20(4), 044054.'
mla: 'Zemlicka, Martin, et al. “Compact Vacuum-Gap Transmon Qubits: Selective and
Sensitive Probes for Superconductor Surface Losses.” Physical Review Applied,
vol. 20, no. 4, 044054, American Physical Society, 2023, doi:10.1103/PhysRevApplied.20.044054.'
short: M. Zemlicka, E. Redchenko, M. Peruzzo, F. Hassani, A. Trioni, S. Barzanjeh,
J.M. Fink, Physical Review Applied 20 (2023).
date_created: 2023-11-12T23:00:55Z
date_published: 2023-10-20T00:00:00Z
date_updated: 2024-08-07T07:11:55Z
day: '20'
department:
- _id: JoFi
doi: 10.1103/PhysRevApplied.20.044054
ec_funded: 1
external_id:
arxiv:
- '2206.14104'
intvolume: ' 20'
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2206.14104
month: '10'
oa: 1
oa_version: Preprint
project:
- _id: 26927A52-B435-11E9-9278-68D0E5697425
call_identifier: FWF
grant_number: F07105
name: Integrating superconducting quantum circuits
- _id: 26336814-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '758053'
name: A Fiber Optic Transceiver for Superconducting Qubits
- _id: eb9b30ac-77a9-11ec-83b8-871f581d53d2
name: Protected states of quantum matter
- _id: 258047B6-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '707438'
name: 'Microwave-to-Optical Quantum Link: Quantum Teleportation and Quantum Illumination
with cavity Optomechanics SUPEREOM'
- _id: bdb7cfc1-d553-11ed-ba76-d2eaab167738
grant_number: '101080139'
name: Open Superconducting Quantum Computers (OpenSuperQPlus)
publication: Physical Review Applied
publication_identifier:
eissn:
- 2331-7019
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
related_material:
record:
- id: '14520'
relation: research_data
status: public
scopus_import: '1'
status: public
title: 'Compact vacuum-gap transmon qubits: Selective and sensitive probes for superconductor
surface losses'
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 20
year: '2023'
...
---
_id: '13117'
abstract:
- lang: eng
text: The ability to control the direction of scattered light is crucial to provide
flexibility and scalability for a wide range of on-chip applications, such as
integrated photonics, quantum information processing, and nonlinear optics. Tunable
directionality can be achieved by applying external magnetic fields that modify
optical selection rules, by using nonlinear effects, or interactions with vibrations.
However, these approaches are less suitable to control microwave photon propagation
inside integrated superconducting quantum devices. Here, we demonstrate on-demand
tunable directional scattering based on two periodically modulated transmon qubits
coupled to a transmission line at a fixed distance. By changing the relative phase
between the modulation tones, we realize unidirectional forward or backward photon
scattering. Such an in-situ switchable mirror represents a versatile tool for
intra- and inter-chip microwave photonic processors. In the future, a lattice
of qubits can be used to realize topological circuits that exhibit strong nonreciprocity
or chirality.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: The authors thank W.D. Oliver for discussions, L. Drmic and P. Zielinski
for software development, and the MIBA workshop and the IST nanofabrication facility
for technical support. This work was supported by the Austrian Science Fund (FWF)
through BeyondC (F7105) and IST Austria. E.R. is the recipient of a DOC fellowship
of the Austrian Academy of Sciences at IST Austria. J.M.F. and M.Z. acknowledge
support from the European Research Council under grant agreement No 758053 (ERC
StG QUNNECT) and a NOMIS foundation research grant. The work of A.N.P. and A.V.P.
has been supported by the Russian Science Foundation under the grant No 20-12-00194.
article_number: '2998'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Elena
full_name: Redchenko, Elena
id: 2C21D6E8-F248-11E8-B48F-1D18A9856A87
last_name: Redchenko
- first_name: Alexander V.
full_name: Poshakinskiy, Alexander V.
last_name: Poshakinskiy
- first_name: Riya
full_name: Sett, Riya
id: 2E6D040E-F248-11E8-B48F-1D18A9856A87
last_name: Sett
- first_name: Martin
full_name: Zemlicka, Martin
id: 2DCF8DE6-F248-11E8-B48F-1D18A9856A87
last_name: Zemlicka
- first_name: Alexander N.
full_name: Poddubny, Alexander N.
last_name: Poddubny
- first_name: Johannes M
full_name: Fink, Johannes M
id: 4B591CBA-F248-11E8-B48F-1D18A9856A87
last_name: Fink
orcid: 0000-0001-8112-028X
citation:
ama: Redchenko E, Poshakinskiy AV, Sett R, Zemlicka M, Poddubny AN, Fink JM. Tunable
directional photon scattering from a pair of superconducting qubits. Nature
Communications. 2023;14. doi:10.1038/s41467-023-38761-6
apa: Redchenko, E., Poshakinskiy, A. V., Sett, R., Zemlicka, M., Poddubny, A. N.,
& Fink, J. M. (2023). Tunable directional photon scattering from a pair of
superconducting qubits. Nature Communications. Springer Nature. https://doi.org/10.1038/s41467-023-38761-6
chicago: Redchenko, Elena, Alexander V. Poshakinskiy, Riya Sett, Martin Zemlicka,
Alexander N. Poddubny, and Johannes M Fink. “Tunable Directional Photon Scattering
from a Pair of Superconducting Qubits.” Nature Communications. Springer
Nature, 2023. https://doi.org/10.1038/s41467-023-38761-6.
ieee: E. Redchenko, A. V. Poshakinskiy, R. Sett, M. Zemlicka, A. N. Poddubny, and
J. M. Fink, “Tunable directional photon scattering from a pair of superconducting
qubits,” Nature Communications, vol. 14. Springer Nature, 2023.
ista: Redchenko E, Poshakinskiy AV, Sett R, Zemlicka M, Poddubny AN, Fink JM. 2023.
Tunable directional photon scattering from a pair of superconducting qubits. Nature
Communications. 14, 2998.
mla: Redchenko, Elena, et al. “Tunable Directional Photon Scattering from a Pair
of Superconducting Qubits.” Nature Communications, vol. 14, 2998, Springer
Nature, 2023, doi:10.1038/s41467-023-38761-6.
short: E. Redchenko, A.V. Poshakinskiy, R. Sett, M. Zemlicka, A.N. Poddubny, J.M.
Fink, Nature Communications 14 (2023).
date_created: 2023-06-04T22:01:02Z
date_published: 2023-05-24T00:00:00Z
date_updated: 2024-08-07T07:11:50Z
day: '24'
ddc:
- '530'
department:
- _id: JoFi
doi: 10.1038/s41467-023-38761-6
ec_funded: 1
external_id:
arxiv:
- '2205.03293'
isi:
- '001001099700002'
file:
- access_level: open_access
checksum: a857df40f0882859c48a1ff1e2001ec2
content_type: application/pdf
creator: dernst
date_created: 2023-06-06T07:31:20Z
date_updated: 2023-06-06T07:31:20Z
file_id: '13123'
file_name: 2023_NaturePhysics_Redchenko.pdf
file_size: 1654389
relation: main_file
success: 1
file_date_updated: 2023-06-06T07:31:20Z
has_accepted_license: '1'
intvolume: ' 14'
isi: 1
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '05'
oa: 1
oa_version: Published Version
project:
- _id: 26927A52-B435-11E9-9278-68D0E5697425
call_identifier: FWF
grant_number: F07105
name: Integrating superconducting quantum circuits
- _id: 26336814-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '758053'
name: A Fiber Optic Transceiver for Superconducting Qubits
- _id: 26B354CA-B435-11E9-9278-68D0E5697425
name: Controllable Collective States of Superconducting Qubit Ensembles
- _id: eb9b30ac-77a9-11ec-83b8-871f581d53d2
name: Protected states of quantum matter
publication: Nature Communications
publication_identifier:
eissn:
- 2041-1723
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
record:
- id: '13124'
relation: research_data
status: public
scopus_import: '1'
status: public
title: Tunable directional photon scattering from a pair of superconducting qubits
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: 14
year: '2023'
...
---
_id: '14032'
abstract:
- lang: eng
text: Arrays of Josephson junctions are governed by a competition between superconductivity
and repulsive Coulomb interactions, and are expected to exhibit diverging low-temperature
resistance when interactions exceed a critical level. Here we report a study of
the transport and microwave response of Josephson arrays with interactions exceeding
this level. Contrary to expectations, we observe that the array resistance drops
dramatically as the temperature is decreased—reminiscent of superconducting behaviour—and
then saturates at low temperature. Applying a magnetic field, we eventually observe
a transition to a highly resistive regime. These observations can be understood
within a theoretical picture that accounts for the effect of thermal fluctuations
on the insulating phase. On the basis of the agreement between experiment and
theory, we suggest that apparent superconductivity in our Josephson arrays arises
from melting the zero-temperature insulator.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: We thank D. Haviland, J. Pekola, C. Ciuti, A. Bubis and A. Shnirman
for helpful feedback on the paper. This research was supported by the Scientific
Service Units of IST Austria through resources provided by the MIBA Machine Shop
and the Nanofabrication Facility. Work supported by the Austrian FWF grant P33692-N
(S.M., J.S. and A.P.H.), the European Union’s Horizon 2020 Research and Innovation
programme under the Marie Skłodowska-Curie Grant Agreement No. 754411 (J.S.) and
a NOMIS foundation research grant (J.M.F. and A.P.H.).
article_processing_charge: Yes (in subscription journal)
article_type: original
author:
- first_name: Soham
full_name: Mukhopadhyay, Soham
id: FDE60288-A89D-11E9-947F-1AF6E5697425
last_name: Mukhopadhyay
- first_name: Jorden L
full_name: Senior, Jorden L
id: 5479D234-2D30-11EA-89CC-40953DDC885E
last_name: Senior
orcid: 0000-0002-0672-9295
- first_name: Jaime
full_name: Saez Mollejo, Jaime
id: e0390f72-f6e0-11ea-865d-862393336714
last_name: Saez Mollejo
- first_name: Denise
full_name: Puglia, Denise
id: 4D495994-AE37-11E9-AC72-31CAE5697425
last_name: Puglia
orcid: 0000-0003-1144-2763
- first_name: Martin
full_name: Zemlicka, Martin
id: 2DCF8DE6-F248-11E8-B48F-1D18A9856A87
last_name: Zemlicka
- first_name: Johannes M
full_name: Fink, Johannes M
id: 4B591CBA-F248-11E8-B48F-1D18A9856A87
last_name: Fink
orcid: 0000-0001-8112-028X
- first_name: Andrew P
full_name: Higginbotham, Andrew P
id: 4AD6785A-F248-11E8-B48F-1D18A9856A87
last_name: Higginbotham
orcid: 0000-0003-2607-2363
citation:
ama: Mukhopadhyay S, Senior JL, Saez Mollejo J, et al. Superconductivity from a
melted insulator in Josephson junction arrays. Nature Physics. 2023;19:1630-1635.
doi:10.1038/s41567-023-02161-w
apa: Mukhopadhyay, S., Senior, J. L., Saez Mollejo, J., Puglia, D., Zemlicka, M.,
Fink, J. M., & Higginbotham, A. P. (2023). Superconductivity from a melted
insulator in Josephson junction arrays. Nature Physics. Springer Nature.
https://doi.org/10.1038/s41567-023-02161-w
chicago: Mukhopadhyay, Soham, Jorden L Senior, Jaime Saez Mollejo, Denise Puglia,
Martin Zemlicka, Johannes M Fink, and Andrew P Higginbotham. “Superconductivity
from a Melted Insulator in Josephson Junction Arrays.” Nature Physics.
Springer Nature, 2023. https://doi.org/10.1038/s41567-023-02161-w.
ieee: S. Mukhopadhyay et al., “Superconductivity from a melted insulator
in Josephson junction arrays,” Nature Physics, vol. 19. Springer Nature,
pp. 1630–1635, 2023.
ista: Mukhopadhyay S, Senior JL, Saez Mollejo J, Puglia D, Zemlicka M, Fink JM,
Higginbotham AP. 2023. Superconductivity from a melted insulator in Josephson
junction arrays. Nature Physics. 19, 1630–1635.
mla: Mukhopadhyay, Soham, et al. “Superconductivity from a Melted Insulator in Josephson
Junction Arrays.” Nature Physics, vol. 19, Springer Nature, 2023, pp. 1630–35,
doi:10.1038/s41567-023-02161-w.
short: S. Mukhopadhyay, J.L. Senior, J. Saez Mollejo, D. Puglia, M. Zemlicka, J.M.
Fink, A.P. Higginbotham, Nature Physics 19 (2023) 1630–1635.
date_created: 2023-08-11T07:41:17Z
date_published: 2023-11-01T00:00:00Z
date_updated: 2024-01-29T11:27:49Z
day: '01'
ddc:
- '530'
department:
- _id: GradSch
- _id: AnHi
- _id: JoFi
doi: 10.1038/s41567-023-02161-w
ec_funded: 1
external_id:
isi:
- '001054563800006'
file:
- access_level: open_access
checksum: 1fc86d71bfbf836e221c1e925343adc5
content_type: application/pdf
creator: dernst
date_created: 2024-01-29T11:25:38Z
date_updated: 2024-01-29T11:25:38Z
file_id: '14899'
file_name: 2023_NaturePhysics_Mukhopadhyay.pdf
file_size: 1977706
relation: main_file
success: 1
file_date_updated: 2024-01-29T11:25:38Z
has_accepted_license: '1'
intvolume: ' 19'
isi: 1
keyword:
- General Physics and Astronomy
language:
- iso: eng
month: '11'
oa: 1
oa_version: Published Version
page: 1630-1635
project:
- _id: 0aa3608a-070f-11eb-9043-e9cd8a2bd931
grant_number: P33692
name: Cavity electromechanics across a quantum phase transition
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
- _id: eb9b30ac-77a9-11ec-83b8-871f581d53d2
name: Protected states of quantum matter
- _id: bd5b4ec5-d553-11ed-ba76-a6eedb083344
name: Protected states of quantum matter
publication: Nature Physics
publication_identifier:
eissn:
- 1745-2481
issn:
- 1745-2473
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Superconductivity from a melted insulator in Josephson junction arrays
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: 19
year: '2023'
...