---
_id: '8911'
abstract:
- lang: eng
text: "In the worldwide endeavor for disruptive quantum technologies, germanium
is emerging as a versatile material to realize devices capable of encoding, processing,
or transmitting quantum information. These devices leverage special properties
of the germanium valence-band states, commonly known as holes, such as their inherently
strong spin-orbit coupling and the ability to host superconducting pairing correlations.
In this Review, we initially introduce the physics of holes in low-dimensional
germanium structures with key insights from a theoretical perspective. We then
examine the material science progress underpinning germanium-based planar heterostructures
and nanowires. We review the most significant experimental results demonstrating
key building blocks for quantum technology, such as an electrically driven universal
quantum gate set with spin qubits in quantum dots and superconductor-semiconductor
devices for hybrid quantum systems. We conclude by identifying the most promising
prospects\r\ntoward scalable quantum information processing. "
acknowledgement: "G.S., M.W.,F.A.Z acknowledge financial support from The Netherlands
Organization for Scientific Research (NWO). F.Z., D.L., G.K. acknowledge funding
from the European Union’s Horizon 2020 research and innovation programme under Grand
Agreement Nr. 862046. G.K. acknowledges funding from FP7 ERC Starting Grant 335497,
FWF Y 715-N30, FWF P-30207. S.D. acknowledges support from the European Union’s
Horizon 2020 program under Grant\r\nAgreement No. 81050 and from the Agence Nationale
de la Recherche through the TOPONANO and CMOSQSPIN projects. J.Z. acknowledges support
from the National Key R&D Program of China (Grant No. 2016YFA0301701) and Strategic
Priority Research Program of CAS (Grant No. XDB30000000). D.L. and C.K. acknowledge
the Swiss National Science Foundation and NCCR QSIT."
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Giordano
full_name: Scappucci, Giordano
last_name: Scappucci
- first_name: Christoph
full_name: Kloeffel, Christoph
last_name: Kloeffel
- first_name: Floris A.
full_name: Zwanenburg, Floris A.
last_name: Zwanenburg
- first_name: Daniel
full_name: Loss, Daniel
last_name: Loss
- first_name: Maksym
full_name: Myronov, Maksym
last_name: Myronov
- first_name: Jian-Jun
full_name: Zhang, Jian-Jun
last_name: Zhang
- first_name: Silvano De
full_name: Franceschi, Silvano De
last_name: Franceschi
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
- first_name: Menno
full_name: Veldhorst, Menno
last_name: Veldhorst
citation:
ama: Scappucci G, Kloeffel C, Zwanenburg FA, et al. The germanium quantum information
route. Nature Reviews Materials. 2021;6:926–943. doi:10.1038/s41578-020-00262-z
apa: Scappucci, G., Kloeffel, C., Zwanenburg, F. A., Loss, D., Myronov, M., Zhang,
J.-J., … Veldhorst, M. (2021). The germanium quantum information route. Nature
Reviews Materials. Springer Nature. https://doi.org/10.1038/s41578-020-00262-z
chicago: Scappucci, Giordano, Christoph Kloeffel, Floris A. Zwanenburg, Daniel Loss,
Maksym Myronov, Jian-Jun Zhang, Silvano De Franceschi, Georgios Katsaros, and
Menno Veldhorst. “The Germanium Quantum Information Route.” Nature Reviews
Materials. Springer Nature, 2021. https://doi.org/10.1038/s41578-020-00262-z.
ieee: G. Scappucci et al., “The germanium quantum information route,” Nature
Reviews Materials, vol. 6. Springer Nature, pp. 926–943, 2021.
ista: Scappucci G, Kloeffel C, Zwanenburg FA, Loss D, Myronov M, Zhang J-J, Franceschi
SD, Katsaros G, Veldhorst M. 2021. The germanium quantum information route. Nature
Reviews Materials. 6, 926–943.
mla: Scappucci, Giordano, et al. “The Germanium Quantum Information Route.” Nature
Reviews Materials, vol. 6, Springer Nature, 2021, pp. 926–943, doi:10.1038/s41578-020-00262-z.
short: G. Scappucci, C. Kloeffel, F.A. Zwanenburg, D. Loss, M. Myronov, J.-J. Zhang,
S.D. Franceschi, G. Katsaros, M. Veldhorst, Nature Reviews Materials 6 (2021)
926–943.
date_created: 2020-12-02T10:52:51Z
date_published: 2021-10-01T00:00:00Z
date_updated: 2024-03-07T14:48:57Z
day: '01'
department:
- _id: GeKa
doi: 10.1038/s41578-020-00262-z
ec_funded: 1
external_id:
arxiv:
- '2004.08133'
isi:
- '000600826100003'
intvolume: ' 6'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2004.08133
month: '10'
oa: 1
oa_version: Preprint
page: '926–943 '
project:
- _id: 25517E86-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '335497'
name: Towards Spin qubits and Majorana fermions in Germanium selfassembled hut-wires
- _id: 2552F888-B435-11E9-9278-68D0E5697425
call_identifier: FWF
grant_number: Y00715
name: Loch Spin-Qubits und Majorana-Fermionen in Germanium
- _id: 2641CE5E-B435-11E9-9278-68D0E5697425
call_identifier: FWF
grant_number: P30207
name: Hole spin orbit qubits in Ge quantum wells
publication: Nature Reviews Materials
publication_identifier:
eissn:
- 2058-8437
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: The germanium quantum information route
type: journal_article
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 6
year: '2021'
...
---
_id: '9464'
abstract:
- lang: eng
text: We firstly introduce the self-assembled growth of highly uniform Ge quantum
wires with controllable position, distance and length on patterned Si (001) substrates.
We then present the electrically tunable strong spin-orbit coupling, the first
Ge hole spin qubit and ultrafast operation of hole spin qubit in the Ge/Si quantum
wires.
acknowledgement: This work was supported by the National Key R&D Program of China
(Grant No. 2016YFA0301700) and the ERC Starting Grant no. 335497.
article_number: '9420817'
article_processing_charge: No
author:
- first_name: Fei
full_name: Gao, Fei
last_name: Gao
- first_name: Jie Yin
full_name: Zhang, Jie Yin
last_name: Zhang
- first_name: Jian Huan
full_name: Wang, Jian Huan
last_name: Wang
- first_name: Ming
full_name: Ming, Ming
last_name: Ming
- first_name: Tina
full_name: Wang, Tina
last_name: Wang
- first_name: Jian Jun
full_name: Zhang, Jian Jun
last_name: Zhang
- first_name: Hannes
full_name: Watzinger, Hannes
id: 35DF8E50-F248-11E8-B48F-1D18A9856A87
last_name: Watzinger
- first_name: Josip
full_name: Kukucka, Josip
id: 3F5D8856-F248-11E8-B48F-1D18A9856A87
last_name: Kukucka
- first_name: Lada
full_name: Vukušić, Lada
id: 31E9F056-F248-11E8-B48F-1D18A9856A87
last_name: Vukušić
orcid: 0000-0003-2424-8636
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
- first_name: Ke
full_name: Wang, Ke
last_name: Wang
- first_name: Gang
full_name: Xu, Gang
last_name: Xu
- first_name: Hai Ou
full_name: Li, Hai Ou
last_name: Li
- first_name: Guo Ping
full_name: Guo, Guo Ping
last_name: Guo
citation:
ama: 'Gao F, Zhang JY, Wang JH, et al. Ge/Si quantum wires for quantum computing.
In: 2021 5th IEEE Electron Devices Technology and Manufacturing Conference,
EDTM 2021. IEEE; 2021. doi:10.1109/EDTM50988.2021.9420817'
apa: 'Gao, F., Zhang, J. Y., Wang, J. H., Ming, M., Wang, T., Zhang, J. J., … Guo,
G. P. (2021). Ge/Si quantum wires for quantum computing. In 2021 5th IEEE Electron
Devices Technology and Manufacturing Conference, EDTM 2021. Virtual, Online:
IEEE. https://doi.org/10.1109/EDTM50988.2021.9420817'
chicago: Gao, Fei, Jie Yin Zhang, Jian Huan Wang, Ming Ming, Tina Wang, Jian Jun
Zhang, Hannes Watzinger, et al. “Ge/Si Quantum Wires for Quantum Computing.” In
2021 5th IEEE Electron Devices Technology and Manufacturing Conference, EDTM
2021. IEEE, 2021. https://doi.org/10.1109/EDTM50988.2021.9420817.
ieee: F. Gao et al., “Ge/Si quantum wires for quantum computing,” in 2021
5th IEEE Electron Devices Technology and Manufacturing Conference, EDTM 2021,
Virtual, Online, 2021.
ista: 'Gao F, Zhang JY, Wang JH, Ming M, Wang T, Zhang JJ, Watzinger H, Kukucka
J, Vukušić L, Katsaros G, Wang K, Xu G, Li HO, Guo GP. 2021. Ge/Si quantum wires
for quantum computing. 2021 5th IEEE Electron Devices Technology and Manufacturing
Conference, EDTM 2021. EDTM: IEEE Electron Devices Technology and Manufacturing
Conference, 9420817.'
mla: Gao, Fei, et al. “Ge/Si Quantum Wires for Quantum Computing.” 2021 5th IEEE
Electron Devices Technology and Manufacturing Conference, EDTM 2021, 9420817,
IEEE, 2021, doi:10.1109/EDTM50988.2021.9420817.
short: F. Gao, J.Y. Zhang, J.H. Wang, M. Ming, T. Wang, J.J. Zhang, H. Watzinger,
J. Kukucka, L. Vukušić, G. Katsaros, K. Wang, G. Xu, H.O. Li, G.P. Guo, in:, 2021
5th IEEE Electron Devices Technology and Manufacturing Conference, EDTM 2021,
IEEE, 2021.
conference:
end_date: 2021-04-11
location: Virtual, Online
name: 'EDTM: IEEE Electron Devices Technology and Manufacturing Conference'
start_date: 2021-04-08
date_created: 2021-06-06T22:01:29Z
date_published: 2021-04-08T00:00:00Z
date_updated: 2023-10-03T12:51:59Z
day: '08'
department:
- _id: GeKa
doi: 10.1109/EDTM50988.2021.9420817
ec_funded: 1
external_id:
isi:
- '000675595800006'
isi: 1
language:
- iso: eng
month: '04'
oa_version: None
project:
- _id: 25517E86-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '335497'
name: Towards Spin qubits and Majorana fermions in Germanium selfassembled hut-wires
publication: 2021 5th IEEE Electron Devices Technology and Manufacturing Conference,
EDTM 2021
publication_identifier:
isbn:
- '9781728181769'
publication_status: published
publisher: IEEE
quality_controlled: '1'
scopus_import: '1'
status: public
title: Ge/Si quantum wires for quantum computing
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2021'
...
---
_id: '7541'
abstract:
- lang: eng
text: Semiconductor nanowires have been playing a crucial role in the development
of nanoscale devices for the realization of spin qubits, Majorana fermions, single
photon emitters, nanoprocessors, etc. The monolithic growth of site‐controlled
nanowires is a prerequisite toward the next generation of devices that will require
addressability and scalability. Here, combining top‐down nanofabrication and bottom‐up
self‐assembly, the growth of Ge wires on prepatterned Si (001) substrates with
controllable position, distance, length, and structure is reported. This is achieved
by a novel growth process that uses a SiGe strain‐relaxation template and can
be potentially generalized to other material combinations. Transport measurements
show an electrically tunable spin–orbit coupling, with a spin–orbit length similar
to that of III–V materials. Also, charge sensing between quantum dots in closely
spaced wires is observed, which underlines their potential for the realization
of advanced quantum devices. The reported results open a path toward scalable
qubit devices using nanowires on silicon.
acknowledged_ssus:
- _id: NanoFab
- _id: M-Shop
acknowledgement: 'This work was supported by the National Key R&D Program of China
(Grant Nos. 2016YFA0301701 and 2016YFA0300600), the NSFC (Grant Nos. 11574356, 11434010,
and 11404252), the Strategic Priority Research Program of CAS (Grant No. XDB30000000),
the ERC Starting Grant No. 335497, the FWF P32235 project, and the European Union''s
Horizon 2020 research and innovation program under Grant Agreement #862046. This
research was supported by the Scientific Service Units of IST Austria through resources
provided by the MIBA Machine Shop and the nanofabrication facility. F.L. thanks
support from DOE (Grant No. DE‐FG02‐04ER46148). H.H. thanks the Startup Funding
from Xi''an Jiaotong University.'
article_number: '1906523'
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Fei
full_name: Gao, Fei
last_name: Gao
- first_name: Jian-Huan
full_name: Wang, Jian-Huan
last_name: Wang
- first_name: Hannes
full_name: Watzinger, Hannes
id: 35DF8E50-F248-11E8-B48F-1D18A9856A87
last_name: Watzinger
- first_name: Hao
full_name: Hu, Hao
last_name: Hu
- first_name: Marko J.
full_name: Rančić, Marko J.
last_name: Rančić
- first_name: Jie-Yin
full_name: Zhang, Jie-Yin
last_name: Zhang
- first_name: Ting
full_name: Wang, Ting
last_name: Wang
- first_name: Yuan
full_name: Yao, Yuan
last_name: Yao
- first_name: Gui-Lei
full_name: Wang, Gui-Lei
last_name: Wang
- first_name: Josip
full_name: Kukucka, Josip
id: 3F5D8856-F248-11E8-B48F-1D18A9856A87
last_name: Kukucka
- first_name: Lada
full_name: Vukušić, Lada
id: 31E9F056-F248-11E8-B48F-1D18A9856A87
last_name: Vukušić
orcid: 0000-0003-2424-8636
- first_name: Christoph
full_name: Kloeffel, Christoph
last_name: Kloeffel
- first_name: Daniel
full_name: Loss, Daniel
last_name: Loss
- first_name: Feng
full_name: Liu, Feng
last_name: Liu
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
- first_name: Jian-Jun
full_name: Zhang, Jian-Jun
last_name: Zhang
citation:
ama: Gao F, Wang J-H, Watzinger H, et al. Site-controlled uniform Ge/Si hut wires
with electrically tunable spin-orbit coupling. Advanced Materials. 2020;32(16).
doi:10.1002/adma.201906523
apa: Gao, F., Wang, J.-H., Watzinger, H., Hu, H., Rančić, M. J., Zhang, J.-Y., …
Zhang, J.-J. (2020). Site-controlled uniform Ge/Si hut wires with electrically
tunable spin-orbit coupling. Advanced Materials. Wiley. https://doi.org/10.1002/adma.201906523
chicago: Gao, Fei, Jian-Huan Wang, Hannes Watzinger, Hao Hu, Marko J. Rančić, Jie-Yin
Zhang, Ting Wang, et al. “Site-Controlled Uniform Ge/Si Hut Wires with Electrically
Tunable Spin-Orbit Coupling.” Advanced Materials. Wiley, 2020. https://doi.org/10.1002/adma.201906523.
ieee: F. Gao et al., “Site-controlled uniform Ge/Si hut wires with electrically
tunable spin-orbit coupling,” Advanced Materials, vol. 32, no. 16. Wiley,
2020.
ista: Gao F, Wang J-H, Watzinger H, Hu H, Rančić MJ, Zhang J-Y, Wang T, Yao Y, Wang
G-L, Kukucka J, Vukušić L, Kloeffel C, Loss D, Liu F, Katsaros G, Zhang J-J. 2020.
Site-controlled uniform Ge/Si hut wires with electrically tunable spin-orbit coupling.
Advanced Materials. 32(16), 1906523.
mla: Gao, Fei, et al. “Site-Controlled Uniform Ge/Si Hut Wires with Electrically
Tunable Spin-Orbit Coupling.” Advanced Materials, vol. 32, no. 16, 1906523,
Wiley, 2020, doi:10.1002/adma.201906523.
short: F. Gao, J.-H. Wang, H. Watzinger, H. Hu, M.J. Rančić, J.-Y. Zhang, T. Wang,
Y. Yao, G.-L. Wang, J. Kukucka, L. Vukušić, C. Kloeffel, D. Loss, F. Liu, G. Katsaros,
J.-J. Zhang, Advanced Materials 32 (2020).
date_created: 2020-02-28T09:47:00Z
date_published: 2020-04-23T00:00:00Z
date_updated: 2024-02-21T12:42:12Z
day: '23'
ddc:
- '530'
department:
- _id: GeKa
doi: 10.1002/adma.201906523
ec_funded: 1
external_id:
isi:
- '000516660900001'
file:
- access_level: open_access
checksum: c622737dc295972065782558337124a2
content_type: application/pdf
creator: dernst
date_created: 2020-11-20T10:11:35Z
date_updated: 2020-11-20T10:11:35Z
file_id: '8782'
file_name: 2020_AdvancedMaterials_Gao.pdf
file_size: 5242880
relation: main_file
success: 1
file_date_updated: 2020-11-20T10:11:35Z
has_accepted_license: '1'
intvolume: ' 32'
isi: 1
issue: '16'
language:
- iso: eng
month: '04'
oa: 1
oa_version: Published Version
project:
- _id: 25517E86-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '335497'
name: Towards Spin qubits and Majorana fermions in Germanium selfassembled hut-wires
- _id: 237B3DA4-32DE-11EA-91FC-C7463DDC885E
call_identifier: FWF
grant_number: P32235
name: Towards scalable hut wire quantum devices
- _id: 237E5020-32DE-11EA-91FC-C7463DDC885E
call_identifier: H2020
grant_number: '862046'
name: TOPOLOGICALLY PROTECTED AND SCALABLE QUANTUM BITS
publication: Advanced Materials
publication_identifier:
issn:
- 0935-9648
publication_status: published
publisher: Wiley
quality_controlled: '1'
related_material:
record:
- id: '7996'
relation: dissertation_contains
status: public
- id: '9222'
relation: research_data
status: public
scopus_import: '1'
status: public
title: Site-controlled uniform Ge/Si hut wires with electrically tunable spin-orbit
coupling
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: 32
year: '2020'
...
---
_id: '23'
abstract:
- lang: eng
text: The strong atomistic spin–orbit coupling of holes makes single-shot spin readout
measurements difficult because it reduces the spin lifetimes. By integrating the
charge sensor into a high bandwidth radio frequency reflectometry setup, we were
able to demonstrate single-shot readout of a germanium quantum dot hole spin and
measure the spin lifetime. Hole spin relaxation times of about 90 μs at 500 mT
are reported, with a total readout visibility of about 70%. By analyzing separately
the spin-to-charge conversion and charge readout fidelities, we have obtained
insight into the processes limiting the visibilities of hole spins. The analyses
suggest that high hole visibilities are feasible at realistic experimental conditions,
underlying the potential of hole spins for the realization of viable qubit devices.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
article_processing_charge: No
author:
- first_name: Lada
full_name: Vukušić, Lada
id: 31E9F056-F248-11E8-B48F-1D18A9856A87
last_name: Vukušić
orcid: 0000-0003-2424-8636
- first_name: Josip
full_name: Kukucka, Josip
id: 3F5D8856-F248-11E8-B48F-1D18A9856A87
last_name: Kukucka
- first_name: Hannes
full_name: Watzinger, Hannes
id: 35DF8E50-F248-11E8-B48F-1D18A9856A87
last_name: Watzinger
- first_name: Joshua M
full_name: Milem, Joshua M
id: 4CDE0A96-F248-11E8-B48F-1D18A9856A87
last_name: Milem
- first_name: Friedrich
full_name: Schäffler, Friedrich
last_name: Schäffler
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
citation:
ama: Vukušić L, Kukucka J, Watzinger H, Milem JM, Schäffler F, Katsaros G. Single-shot
readout of hole spins in Ge. Nano Letters. 2018;18(11):7141-7145. doi:10.1021/acs.nanolett.8b03217
apa: Vukušić, L., Kukucka, J., Watzinger, H., Milem, J. M., Schäffler, F., &
Katsaros, G. (2018). Single-shot readout of hole spins in Ge. Nano Letters.
American Chemical Society. https://doi.org/10.1021/acs.nanolett.8b03217
chicago: Vukušić, Lada, Josip Kukucka, Hannes Watzinger, Joshua M Milem, Friedrich
Schäffler, and Georgios Katsaros. “Single-Shot Readout of Hole Spins in Ge.” Nano
Letters. American Chemical Society, 2018. https://doi.org/10.1021/acs.nanolett.8b03217.
ieee: L. Vukušić, J. Kukucka, H. Watzinger, J. M. Milem, F. Schäffler, and G. Katsaros,
“Single-shot readout of hole spins in Ge,” Nano Letters, vol. 18, no. 11.
American Chemical Society, pp. 7141–7145, 2018.
ista: Vukušić L, Kukucka J, Watzinger H, Milem JM, Schäffler F, Katsaros G. 2018.
Single-shot readout of hole spins in Ge. Nano Letters. 18(11), 7141–7145.
mla: Vukušić, Lada, et al. “Single-Shot Readout of Hole Spins in Ge.” Nano Letters,
vol. 18, no. 11, American Chemical Society, 2018, pp. 7141–45, doi:10.1021/acs.nanolett.8b03217.
short: L. Vukušić, J. Kukucka, H. Watzinger, J.M. Milem, F. Schäffler, G. Katsaros,
Nano Letters 18 (2018) 7141–7145.
date_created: 2018-12-11T11:44:13Z
date_published: 2018-10-25T00:00:00Z
date_updated: 2023-09-18T09:30:37Z
day: '25'
ddc:
- '530'
department:
- _id: GeKa
doi: 10.1021/acs.nanolett.8b03217
ec_funded: 1
external_id:
isi:
- '000451102100064'
pmid:
- '30359041'
file:
- access_level: open_access
checksum: 3e6034a94c6b5335e939145d88bdb371
content_type: application/pdf
creator: system
date_created: 2018-12-12T10:16:08Z
date_updated: 2020-07-14T12:45:37Z
file_id: '5194'
file_name: IST-2018-1065-v1+1_ACS_nanoletters_8b03217.pdf
file_size: 1361441
relation: main_file
file_date_updated: 2020-07-14T12:45:37Z
has_accepted_license: '1'
intvolume: ' 18'
isi: 1
issue: '11'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
page: 7141 - 7145
pmid: 1
project:
- _id: 25517E86-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '335497'
name: Towards Spin qubits and Majorana fermions in Germanium selfassembled hut-wires
publication: Nano Letters
publication_identifier:
issn:
- '15306984'
publication_status: published
publisher: American Chemical Society
publist_id: '8032'
pubrep_id: '1065'
quality_controlled: '1'
related_material:
record:
- id: '7977'
relation: popular_science
- id: '69'
relation: dissertation_contains
status: public
- id: '7996'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Single-shot readout of hole spins in Ge
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: 18
year: '2018'
...
---
_id: '77'
abstract:
- lang: eng
text: Holes confined in quantum dots have gained considerable interest in the past
few years due to their potential as spin qubits. Here we demonstrate two-axis
control of a spin 3/2 qubit in natural Ge. The qubit is formed in a hut wire double
quantum dot device. The Pauli spin blockade principle allowed us to demonstrate
electric dipole spin resonance by applying a radio frequency electric field to
one of the electrodes defining the double quantum dot. Coherent hole spin oscillations
with Rabi frequencies reaching 140 MHz are demonstrated and dephasing times of
130 ns are measured. The reported results emphasize the potential of Ge as a platform
for fast and electrically tunable hole spin qubit devices.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
article_processing_charge: Yes
article_type: original
author:
- first_name: Hannes
full_name: Watzinger, Hannes
id: 35DF8E50-F248-11E8-B48F-1D18A9856A87
last_name: Watzinger
- first_name: Josip
full_name: Kukucka, Josip
id: 3F5D8856-F248-11E8-B48F-1D18A9856A87
last_name: Kukucka
- first_name: Lada
full_name: Vukusic, Lada
id: 31E9F056-F248-11E8-B48F-1D18A9856A87
last_name: Vukusic
orcid: 0000-0003-2424-8636
- first_name: Fei
full_name: Gao, Fei
last_name: Gao
- first_name: Ting
full_name: Wang, Ting
last_name: Wang
- first_name: Friedrich
full_name: Schäffler, Friedrich
last_name: Schäffler
- first_name: Jian
full_name: Zhang, Jian
last_name: Zhang
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
citation:
ama: Watzinger H, Kukucka J, Vukušić L, et al. A germanium hole spin qubit. Nature
Communications. 2018;9(3902). doi:10.1038/s41467-018-06418-4
apa: Watzinger, H., Kukucka, J., Vukušić, L., Gao, F., Wang, T., Schäffler, F.,
… Katsaros, G. (2018). A germanium hole spin qubit. Nature Communications.
Nature Publishing Group. https://doi.org/10.1038/s41467-018-06418-4
chicago: Watzinger, Hannes, Josip Kukucka, Lada Vukušić, Fei Gao, Ting Wang, Friedrich
Schäffler, Jian Zhang, and Georgios Katsaros. “A Germanium Hole Spin Qubit.” Nature
Communications. Nature Publishing Group, 2018. https://doi.org/10.1038/s41467-018-06418-4.
ieee: H. Watzinger et al., “A germanium hole spin qubit,” Nature Communications,
vol. 9, no. 3902. Nature Publishing Group, 2018.
ista: Watzinger H, Kukucka J, Vukušić L, Gao F, Wang T, Schäffler F, Zhang J, Katsaros
G. 2018. A germanium hole spin qubit. Nature Communications. 9(3902).
mla: Watzinger, Hannes, et al. “A Germanium Hole Spin Qubit.” Nature Communications,
vol. 9, no. 3902, Nature Publishing Group, 2018, doi:10.1038/s41467-018-06418-4.
short: H. Watzinger, J. Kukucka, L. Vukušić, F. Gao, T. Wang, F. Schäffler, J. Zhang,
G. Katsaros, Nature Communications 9 (2018).
date_created: 2018-12-11T11:44:30Z
date_published: 2018-09-25T00:00:00Z
date_updated: 2023-09-08T11:44:02Z
day: '25'
ddc:
- '530'
department:
- _id: GeKa
doi: 10.1038/s41467-018-06418-4
ec_funded: 1
external_id:
isi:
- '000445560800010'
file:
- access_level: open_access
checksum: e7148c10a64497e279c4de570b6cc544
content_type: application/pdf
creator: dernst
date_created: 2018-12-17T10:28:30Z
date_updated: 2020-07-14T12:48:02Z
file_id: '5687'
file_name: 2018_NatureComm_Watzinger.pdf
file_size: 1063469
relation: main_file
file_date_updated: 2020-07-14T12:48:02Z
has_accepted_license: '1'
intvolume: ' 9'
isi: 1
issue: '3902 '
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
project:
- _id: 25517E86-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '335497'
name: Towards Spin qubits and Majorana fermions in Germanium selfassembled hut-wires
- _id: 2552F888-B435-11E9-9278-68D0E5697425
call_identifier: FWF
grant_number: Y00715
name: Loch Spin-Qubits und Majorana-Fermionen in Germanium
publication: Nature Communications
publication_status: published
publisher: Nature Publishing Group
quality_controlled: '1'
related_material:
record:
- id: '7977'
relation: popular_science
- id: '7996'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: A germanium hole spin qubit
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: 9
year: '2018'
...
---
_id: '840'
abstract:
- lang: eng
text: Heavy holes confined in quantum dots are predicted to be promising candidates
for the realization of spin qubits with long coherence times. Here we focus on
such heavy-hole states confined in germanium hut wires. By tuning the growth density
of the latter we can realize a T-like structure between two neighboring wires.
Such a structure allows the realization of a charge sensor, which is electrostatically
and tunnel coupled to a quantum dot, with charge-transfer signals as high as 0.3
e. By integrating the T-like structure into a radiofrequency reflectometry setup,
single-shot measurements allowing the extraction of hole tunneling times are performed.
The extracted tunneling times of less than 10 μs are attributed to the small effective
mass of Ge heavy-hole states and pave the way toward projective spin readout measurements.
acknowledged_ssus:
- _id: M-Shop
article_processing_charge: No
author:
- first_name: Lada
full_name: Vukusic, Lada
id: 31E9F056-F248-11E8-B48F-1D18A9856A87
last_name: Vukusic
orcid: 0000-0003-2424-8636
- first_name: Josip
full_name: Kukucka, Josip
id: 3F5D8856-F248-11E8-B48F-1D18A9856A87
last_name: Kukucka
- first_name: Hannes
full_name: Watzinger, Hannes
id: 35DF8E50-F248-11E8-B48F-1D18A9856A87
last_name: Watzinger
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
citation:
ama: Vukušić L, Kukucka J, Watzinger H, Katsaros G. Fast hole tunneling times in
germanium hut wires probed by single-shot reflectometry. Nano Letters.
2017;17(9):5706-5710. doi:10.1021/acs.nanolett.7b02627
apa: Vukušić, L., Kukucka, J., Watzinger, H., & Katsaros, G. (2017). Fast hole
tunneling times in germanium hut wires probed by single-shot reflectometry. Nano
Letters. American Chemical Society. https://doi.org/10.1021/acs.nanolett.7b02627
chicago: Vukušić, Lada, Josip Kukucka, Hannes Watzinger, and Georgios Katsaros.
“Fast Hole Tunneling Times in Germanium Hut Wires Probed by Single-Shot Reflectometry.”
Nano Letters. American Chemical Society, 2017. https://doi.org/10.1021/acs.nanolett.7b02627.
ieee: L. Vukušić, J. Kukucka, H. Watzinger, and G. Katsaros, “Fast hole tunneling
times in germanium hut wires probed by single-shot reflectometry,” Nano Letters,
vol. 17, no. 9. American Chemical Society, pp. 5706–5710, 2017.
ista: Vukušić L, Kukucka J, Watzinger H, Katsaros G. 2017. Fast hole tunneling times
in germanium hut wires probed by single-shot reflectometry. Nano Letters. 17(9),
5706–5710.
mla: Vukušić, Lada, et al. “Fast Hole Tunneling Times in Germanium Hut Wires Probed
by Single-Shot Reflectometry.” Nano Letters, vol. 17, no. 9, American Chemical
Society, 2017, pp. 5706–10, doi:10.1021/acs.nanolett.7b02627.
short: L. Vukušić, J. Kukucka, H. Watzinger, G. Katsaros, Nano Letters 17 (2017)
5706–5710.
date_created: 2018-12-11T11:48:47Z
date_published: 2017-08-10T00:00:00Z
date_updated: 2023-09-26T15:50:22Z
day: '10'
ddc:
- '539'
department:
- _id: GeKa
doi: 10.1021/acs.nanolett.7b02627
ec_funded: 1
external_id:
isi:
- '000411043500078'
file:
- access_level: open_access
checksum: 761371a0129b2aa442424b9561450ece
content_type: application/pdf
creator: system
date_created: 2018-12-12T10:12:33Z
date_updated: 2020-07-14T12:48:13Z
file_id: '4951'
file_name: IST-2017-865-v1+1_acs.nanolett.7b02627.pdf
file_size: 2449546
relation: main_file
file_date_updated: 2020-07-14T12:48:13Z
has_accepted_license: '1'
intvolume: ' 17'
isi: 1
issue: '9'
language:
- iso: eng
month: '08'
oa: 1
oa_version: Published Version
page: 5706 - 5710
project:
- _id: 25517E86-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '335497'
name: Towards Spin qubits and Majorana fermions in Germanium selfassembled hut-wires
publication: Nano Letters
publication_identifier:
issn:
- '15306984'
publication_status: published
publisher: American Chemical Society
publist_id: '6808'
pubrep_id: '865'
quality_controlled: '1'
related_material:
record:
- id: '7977'
relation: popular_science
- id: '69'
relation: dissertation_contains
status: public
- id: '7996'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Fast hole tunneling times in germanium hut wires probed by single-shot reflectometry
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: 17
year: '2017'
...
---
_id: '1328'
abstract:
- lang: eng
text: Hole spins have gained considerable interest in the past few years due to
their potential for fast electrically controlled qubits. Here, we study holes
confined in Ge hut wires, a so-far unexplored type of nanostructure. Low-temperature
magnetotransport measurements reveal a large anisotropy between the in-plane and
out-of-plane g-factors of up to 18. Numerical simulations verify that this large
anisotropy originates from a confined wave function of heavy-hole character. A
light-hole admixture of less than 1% is estimated for the states of lowest energy,
leading to a surprisingly large reduction of the out-of-plane g-factors compared
with those for pure heavy holes. Given this tiny light-hole contribution, the
spin lifetimes are expected to be very long, even in isotopically nonpurified
samples.
acknowledgement: 'The work was supported by the EC FP7 ICT project SiSPIN no. 323841,
the EC FP7 ICT project PAMS no. 610446, the ERC Starting Grant no. 335497, the FWF-I-1190-N20
project, and the Swiss NSF. We acknowledge F. Schäffler for fruitful discussions
related to the hut wire growth and for giving us access to the molecular beam epitaxy
system, M. Schatzl for her support in electron beam lithography, and V. Jadris ̌ko
for helping us with the COMSOL simulations. Finally, we thank G. Bauer for his continuous
support. '
author:
- first_name: Hannes
full_name: Watzinger, Hannes
id: 35DF8E50-F248-11E8-B48F-1D18A9856A87
last_name: Watzinger
- first_name: Christoph
full_name: Kloeffel, Christoph
last_name: Kloeffel
- first_name: Lada
full_name: Vukusic, Lada
id: 31E9F056-F248-11E8-B48F-1D18A9856A87
last_name: Vukusic
orcid: 0000-0003-2424-8636
- first_name: Marta
full_name: Rossell, Marta
last_name: Rossell
- first_name: Violetta
full_name: Sessi, Violetta
last_name: Sessi
- first_name: Josip
full_name: Kukucka, Josip
id: 3F5D8856-F248-11E8-B48F-1D18A9856A87
last_name: Kukucka
- first_name: Raimund
full_name: Kirchschlager, Raimund
last_name: Kirchschlager
- first_name: Elisabeth
full_name: Lausecker, Elisabeth
id: 33662F76-F248-11E8-B48F-1D18A9856A87
last_name: Lausecker
- first_name: Alisha
full_name: Truhlar, Alisha
id: 49CBC780-F248-11E8-B48F-1D18A9856A87
last_name: Truhlar
- first_name: Martin
full_name: Glaser, Martin
last_name: Glaser
- first_name: Armando
full_name: Rastelli, Armando
last_name: Rastelli
- first_name: Andreas
full_name: Fuhrer, Andreas
last_name: Fuhrer
- first_name: Daniel
full_name: Loss, Daniel
last_name: Loss
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
citation:
ama: Watzinger H, Kloeffel C, Vukušić L, et al. Heavy-hole states in germanium hut
wires. Nano Letters. 2016;16(11):6879-6885. doi:10.1021/acs.nanolett.6b02715
apa: Watzinger, H., Kloeffel, C., Vukušić, L., Rossell, M., Sessi, V., Kukucka,
J., … Katsaros, G. (2016). Heavy-hole states in germanium hut wires. Nano Letters.
American Chemical Society. https://doi.org/10.1021/acs.nanolett.6b02715
chicago: Watzinger, Hannes, Christoph Kloeffel, Lada Vukušić, Marta Rossell, Violetta
Sessi, Josip Kukucka, Raimund Kirchschlager, et al. “Heavy-Hole States in Germanium
Hut Wires.” Nano Letters. American Chemical Society, 2016. https://doi.org/10.1021/acs.nanolett.6b02715.
ieee: H. Watzinger et al., “Heavy-hole states in germanium hut wires,” Nano
Letters, vol. 16, no. 11. American Chemical Society, pp. 6879–6885, 2016.
ista: Watzinger H, Kloeffel C, Vukušić L, Rossell M, Sessi V, Kukucka J, Kirchschlager
R, Lausecker E, Truhlar A, Glaser M, Rastelli A, Fuhrer A, Loss D, Katsaros G.
2016. Heavy-hole states in germanium hut wires. Nano Letters. 16(11), 6879–6885.
mla: Watzinger, Hannes, et al. “Heavy-Hole States in Germanium Hut Wires.” Nano
Letters, vol. 16, no. 11, American Chemical Society, 2016, pp. 6879–85, doi:10.1021/acs.nanolett.6b02715.
short: H. Watzinger, C. Kloeffel, L. Vukušić, M. Rossell, V. Sessi, J. Kukucka,
R. Kirchschlager, E. Lausecker, A. Truhlar, M. Glaser, A. Rastelli, A. Fuhrer,
D. Loss, G. Katsaros, Nano Letters 16 (2016) 6879–6885.
date_created: 2018-12-11T11:51:24Z
date_published: 2016-09-22T00:00:00Z
date_updated: 2023-09-07T13:15:02Z
day: '22'
ddc:
- '539'
department:
- _id: GeKa
doi: 10.1021/acs.nanolett.6b02715
ec_funded: 1
file:
- access_level: open_access
checksum: b63feece90d7b620ece49ca632e34ff3
content_type: application/pdf
creator: system
date_created: 2018-12-12T10:14:04Z
date_updated: 2020-07-14T12:44:44Z
file_id: '5053'
file_name: IST-2016-664-v1+1_acs.nanolett.6b02715.pdf
file_size: 535121
relation: main_file
file_date_updated: 2020-07-14T12:44:44Z
has_accepted_license: '1'
intvolume: ' 16'
issue: '11'
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
page: 6879 - 6885
project:
- _id: 25517E86-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '335497'
name: Towards Spin qubits and Majorana fermions in Germanium selfassembled hut-wires
publication: Nano Letters
publication_status: published
publisher: American Chemical Society
publist_id: '5941'
pubrep_id: '664'
quality_controlled: '1'
related_material:
record:
- id: '7977'
relation: popular_science
status: for_moderation
- id: '7996'
relation: dissertation_contains
status: public
scopus_import: 1
status: public
title: Heavy-hole states in germanium hut wires
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: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 16
year: '2016'
...