---
OA_place: repository
OA_type: green
_id: '22619'
abstract:
- lang: eng
text: Planar germanium is currently the only semiconducting platform where high-coherence
spin qubits and proximity-induced superconductivity have each been demonstrated.
Recent research into spin qubits in Ge/SiGe heterostructures has focused on increasing
the thickness of the SiGe capping layer, reporting improvements in the electrostatic
noise levels. Meanwhile, heterostructures with thinner capping layers remain rather
unexplored, despite the potential advantages for proximity-induced superconductivity.
Here, we study a Ge/SiGe heterostructure with a thin SiGe cap d - 4nm and investigate
its viability to host low-noise quantum dots. To keep the thermal budget compatible
with superconducting layers, low-temperature oxide deposition processes were developed
and implemented for the gate dielectrics. The charge noise level of the fabricated
devices is estimated to be 1.8 +- 1.0 μeV/ square HZ, comparable to devices
fabricated on shallow heterostructures ( d - 20nm) with high-temperature deposited
oxides. Low charge noise levels, together with the straightforward integration
of superconductors, make this heterostructure an attractive platform for prototyping
hybrid semiconducting–superconducting devices.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: 'We sincerely thank Nick van Loo, Greg Mazur, Dhananjay Joshi, and
Srijit Goswami for their inputs on low-temperature HfOx deposition; Matias Urdampilleta
and Daniel Jirovec for discussions; and Kristen Léonard for the careful reading
of the manuscript. This research was supported by the Scientific Service Units of
ISTA through resources provided by the Miba Machine Shop and the Nanofabrication
facility. The authors acknowledge support from the NOMIS Foundation; the European
Innovation Council Pathfinder Grant No. 101115315 (QuKiT); the FWF Projects with
DOI:10.55776/F86, DOI:10.55776/PAT7682124, and DOI:10.55776/P36507; and the HE-MSCA-PF
project with DOI:10.3030/101150858. ICN2 is supported by the Severo Ochoa Program
from Spanish MCIN/AEI (Grant No.: CEX2021-001214-S) and is funded by the CERCA Program/Generalitat
de Catalunya. ICN2 acknowledges funding from Generalitat de Catalunya (No. 2021SGR00457).
We acknowledge support from the CSIC Interdisciplinary Thematic Platform (PTI+)
on Quantum Technologies (PTI-QTEP+).'
article_number: '033505'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Maksim
full_name: Borovkov, Maksim
id: 1fd0975f-8b61-11ed-b69e-d149334f28c5
last_name: Borovkov
- first_name: Yona A
full_name: Schell, Yona A
id: fe39122d-06bb-11ec-a33b-9e22b40e40a5
last_name: Schell
- first_name: Dina
full_name: Sokolova, Dina
id: 2d2d62f8-72f0-11ef-b75a-8ec3e8a60032
last_name: Sokolova
- first_name: Kevin Etienne Robert
full_name: Roux, Kevin Etienne Robert
id: 53f93ea2-803f-11ed-ab7e-b283135794ef
last_name: Roux
- first_name: Paul
full_name: Falthansl-Scheinecker, Paul
id: 85b43b21-15b2-11ec-abd3-e2c252cc2285
last_name: Falthansl-Scheinecker
- first_name: Giorgio
full_name: Fabris, Giorgio
id: 298cf6f3-1ff6-11ee-9fa6-d94cfa0b3352
last_name: Fabris
- first_name: Devashish C
full_name: Shah, Devashish C
id: de191434-4e7e-11ef-bf4b-9a056fc19fc3
last_name: Shah
orcid: 0009-0007-5829-7707
- first_name: Jaime
full_name: Saez Mollejo, Jaime
id: e0390f72-f6e0-11ea-865d-862393336714
last_name: Saez Mollejo
- first_name: Rodolfo
full_name: Previdi, Rodolfo
id: bc4ea1dc-00ce-11ec-8a4e-b325ca8b9876
last_name: Previdi
- first_name: Inas
full_name: Taha, Inas
last_name: Taha
- first_name: Aziz
full_name: Genç, Aziz
last_name: Genç
- first_name: Jordi
full_name: Arbiol, Jordi
last_name: Arbiol
- first_name: Stefano
full_name: Calcaterra, Stefano
last_name: Calcaterra
- first_name: Afonso De Cerdeira
full_name: Oliveira, Afonso De Cerdeira
last_name: Oliveira
- first_name: Daniel
full_name: Chrastina, Daniel
last_name: Chrastina
- first_name: Giovanni
full_name: Isella, Giovanni
last_name: Isella
- first_name: Anton
full_name: Bubis, Anton
id: 1f6212b5-f795-11ec-9c0c-de4780302890
last_name: Bubis
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
citation:
ama: Borovkov M, Schell YA, Sokolova D, et al. Low-noise quantum dots in ultra-shallow
Ge/SiGe heterostructures for prototyping hybrid semiconducting–superconducting
devices. Applied Physics Letters. 2026;129(3). doi:10.1063/5.0333142
apa: Borovkov, M., Schell, Y. A., Sokolova, D., Roux, K. E. R., Falthansl-Scheinecker,
P., Fabris, G., … Katsaros, G. (2026). Low-noise quantum dots in ultra-shallow
Ge/SiGe heterostructures for prototyping hybrid semiconducting–superconducting
devices. Applied Physics Letters. AIP Publishing. https://doi.org/10.1063/5.0333142
chicago: Borovkov, Maksim, Yona A Schell, Dina Sokolova, Kevin Etienne Robert Roux,
Paul Falthansl-Scheinecker, Giorgio Fabris, Devashish C Shah, et al. “Low-Noise
Quantum Dots in Ultra-Shallow Ge/SiGe Heterostructures for Prototyping Hybrid
Semiconducting–Superconducting Devices.” Applied Physics Letters. AIP Publishing,
2026. https://doi.org/10.1063/5.0333142.
ieee: M. Borovkov et al., “Low-noise quantum dots in ultra-shallow Ge/SiGe
heterostructures for prototyping hybrid semiconducting–superconducting devices,”
Applied Physics Letters, vol. 129, no. 3. AIP Publishing, 2026.
ista: Borovkov M, Schell YA, Sokolova D, Roux KER, Falthansl-Scheinecker P, Fabris
G, Shah DC, Saez Mollejo J, Previdi R, Taha I, Genç A, Arbiol J, Calcaterra S,
Oliveira ADC, Chrastina D, Isella G, Bubis A, Katsaros G. 2026. Low-noise quantum
dots in ultra-shallow Ge/SiGe heterostructures for prototyping hybrid semiconducting–superconducting
devices. Applied Physics Letters. 129(3), 033505.
mla: Borovkov, Maksim, et al. “Low-Noise Quantum Dots in Ultra-Shallow Ge/SiGe Heterostructures
for Prototyping Hybrid Semiconducting–Superconducting Devices.” Applied Physics
Letters, vol. 129, no. 3, 033505, AIP Publishing, 2026, doi:10.1063/5.0333142.
short: M. Borovkov, Y.A. Schell, D. Sokolova, K.E.R. Roux, P. Falthansl-Scheinecker,
G. Fabris, D.C. Shah, J. Saez Mollejo, R. Previdi, I. Taha, A. Genç, J. Arbiol,
S. Calcaterra, A.D.C. Oliveira, D. Chrastina, G. Isella, A. Bubis, G. Katsaros,
Applied Physics Letters 129 (2026).
corr_author: '1'
das_tickbox: '1'
dataavailabilitystatement: The data that support the findings of this study are openly
available in Institute of Science and Technology repository at http://doi.org/10.15479/AT-ISTA-22242,
Ref. 50.
date_created: 2026-08-02T22:01:53Z
date_published: 2026-07-20T00:00:00Z
date_updated: 2026-08-03T11:08:39Z
day: '20'
department:
- _id: GeKa
- _id: GradSch
- _id: NanoFab
doi: 10.1063/5.0333142
external_id:
arxiv:
- '2602.21363'
intvolume: ' 129'
issue: '3'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.48550/arXiv.2602.21363
month: '07'
oa: 1
oa_version: Preprint
project:
- _id: bdc2ca30-d553-11ed-ba76-cf164a5bb811
grant_number: '101115315'
name: Quantum bits with Kitaev Transmons
- _id: 34a66131-11ca-11ed-8bc3-a31681c6b03e
grant_number: F8606
name: 'Center for Correlated Quantum Materials and Solid State Quantum Systems:
Conventional and unconventional topological superconductors'
- _id: 5b9e579c-ab3d-11f0-914f-88754c5b5a3f
grant_number: PAT 7682124
name: Superconducting spin qubits in planar Ge
- _id: bd8bd29e-d553-11ed-ba76-f0070d4b237a
grant_number: P36507
name: Merging spin and superconducting qubits in planar Ge
- _id: 8ea8abf7-16d5-11f0-9cad-c41e56ec8bb3
grant_number: '101150858'
name: Realization and Manipulation of a Planar hybrid superconducting Andreev spin
qubit in Germanium
publication: Applied Physics Letters
publication_identifier:
eissn:
- 1077-3118
issn:
- 0003-6951
publication_status: published
publisher: AIP Publishing
quality_controlled: '1'
related_material:
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researchdata_availability: yes
scopus_import: '1'
status: public
supplementarymaterial: yes
title: Low-noise quantum dots in ultra-shallow Ge/SiGe heterostructures for prototyping
hybrid semiconducting–superconducting devices
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 129
year: '2026'
...
---
OA_place: publisher
OA_type: gold
_id: '19409'
abstract:
- lang: eng
text: "This .zip file contains the data to reproduce the figures and supplementary
figures of \"Exchange anisotropies in microwave-driven singlet-triplet qubits\"
by Jaime Saez-Mollejo et al.\r\n"
acknowledged_ssus:
- _id: NanoFab
- _id: M-Shop
acknowledgement: "We thank A. Crippa for helpful discussions. This research was supported
by the Scientific Service Units of ISTA through resources provided by the MIBA Machine
Shop and the Nanofabrication facility. This research and related results were made
possible with the support of the NOMIS Foundation, the HORIZON-RIA 101069515 project
and the FWF Projects \r\nwith DOI:10.55776/F86 and DOI:10.55776/I5060. M.R.-R. acknowledges
support from the Netherlands Organization of\r\n scientific Research (NWO) under
Veni grant VI.Veni.212.223. The Research of S.B. and M.R.-R. was sponsored in part
by the Army Research Office and was accomplished under Award Number: W911NF-23-1-0110."
article_processing_charge: No
author:
- first_name: Jaime
full_name: Saez Mollejo, Jaime
id: e0390f72-f6e0-11ea-865d-862393336714
last_name: Saez Mollejo
citation:
ama: Saez Mollejo J. Exchange anisotropies in microwave-driven singlet-triplet qubits.
2025. doi:10.15479/AT:ISTA:19409
apa: Saez Mollejo, J. (2025). Exchange anisotropies in microwave-driven singlet-triplet
qubits. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:19409
chicago: Saez Mollejo, Jaime. “Exchange Anisotropies in Microwave-Driven Singlet-Triplet
Qubits.” Institute of Science and Technology Austria, 2025. https://doi.org/10.15479/AT:ISTA:19409.
ieee: J. Saez Mollejo, “Exchange anisotropies in microwave-driven singlet-triplet
qubits.” Institute of Science and Technology Austria, 2025.
ista: Saez Mollejo J. 2025. Exchange anisotropies in microwave-driven singlet-triplet
qubits, Institute of Science and Technology Austria, 10.15479/AT:ISTA:19409.
mla: Saez Mollejo, Jaime. Exchange Anisotropies in Microwave-Driven Singlet-Triplet
Qubits. Institute of Science and Technology Austria, 2025, doi:10.15479/AT:ISTA:19409.
short: J. Saez Mollejo, (2025).
contributor:
- first_name: Daniel
id: 4C473F58-F248-11E8-B48F-1D18A9856A87
last_name: Jirovec
orcid: 0000-0002-7197-4801
- first_name: Yona A
id: fe39122d-06bb-11ec-a33b-9e22b40e40a5
last_name: Schell
- first_name: Josip
id: 3F5D8856-F248-11E8-B48F-1D18A9856A87
last_name: Kukucka
- first_name: Stefano
last_name: Calcaterra
- first_name: 'Daniel '
last_name: Chrastina
- first_name: 'Giovanni '
last_name: Isella
- first_name: Maximilian
last_name: Rimbach-Russ
- first_name: Stefano
last_name: Bosco
- first_name: Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
corr_author: '1'
date_created: 2025-03-17T08:57:09Z
date_published: 2025-03-17T00:00:00Z
date_updated: 2026-05-20T06:42:16Z
day: '17'
ddc:
- '530'
department:
- _id: GradSch
- _id: GeKa
doi: 10.15479/AT:ISTA:19409
file:
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checksum: 1f21c8ea2196776aae51cc3a5d00e00b
content_type: application/x-zip-compressed
creator: jsaezmol
date_created: 2025-03-17T08:48:09Z
date_updated: 2025-03-17T08:48:09Z
file_id: '19410'
file_name: AllDataPublished.zip
file_size: 21971911
relation: main_file
success: 1
file_date_updated: 2025-03-17T08:48:09Z
has_accepted_license: '1'
license: https://creativecommons.org/licenses/by/4.0/
month: '03'
oa: 1
oa_version: Published Version
project:
- _id: 34c0acea-11ca-11ed-8bc3-8775e10fd452
grant_number: '101069515'
name: Integrated Germanium Quantum Technology
- _id: c0977eea-5a5b-11eb-8a69-a862db0cf4d1
grant_number: I05060
name: High impedance circuit quantum electrodynamics with hole spins
- _id: 34a66131-11ca-11ed-8bc3-a31681c6b03e
grant_number: F8606
name: 'Center for Correlated Quantum Materials and Solid State Quantum Systems:
Conventional and unconventional topological superconductors'
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '19424'
relation: used_in_publication
status: public
status: public
title: Exchange anisotropies in microwave-driven singlet-triplet 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: research_data
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2025'
...
---
_id: '19885'
abstract:
- lang: eng
text: This .zip file contains the data to reproduce the figures and supplementary
figures of "Automated All-RF Tuning for Spin Qubit Readout and Control" by Cornelius
Carlsson and Jaime Saez-Mollejo et al.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: 'The authors would like to thank Barnaby van Straaten, Jonas Schuff,
Daniel Jirovec and Hanifa Tidjani for fruitful discussions. This research was supported
by the Scientific Service Units of ISTA through resources provided by the MIBA Machine
Shop and the Nanofabrication Facility. G.K. acknowledges support from the NOMIS
Foundation, the HORIZON-RIA (project no. 101069515) and the FWF Projects (DOIs:
10.55776/F86 and 10.55776/I5060). N.A. acknowledges support from the European Research
Council (grant agreement 948932), and the Royal Society (grant no. URF/R1/191150).
This project received support from the US Army Research Office (ARO) under Award
No. W911NF-24-2-0043. C.C. acknowledges support from the UKRI Doctoral Training
Partnership related to EP/W524311/1 (project ref. 2887634).'
article_processing_charge: No
author:
- first_name: Jaime
full_name: Saez Mollejo, Jaime
id: e0390f72-f6e0-11ea-865d-862393336714
last_name: Saez Mollejo
citation:
ama: Saez Mollejo J. Automated All-RF Tuning for Spin Qubit Readout and Control.
2025. doi:10.15479/AT:ISTA:19885
apa: Saez Mollejo, J. (2025). Automated All-RF Tuning for Spin Qubit Readout and
Control. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:19885
chicago: Saez Mollejo, Jaime. “Automated All-RF Tuning for Spin Qubit Readout and
Control.” Institute of Science and Technology Austria, 2025. https://doi.org/10.15479/AT:ISTA:19885.
ieee: J. Saez Mollejo, “Automated All-RF Tuning for Spin Qubit Readout and Control.”
Institute of Science and Technology Austria, 2025.
ista: Saez Mollejo J. 2025. Automated All-RF Tuning for Spin Qubit Readout and Control,
Institute of Science and Technology Austria, 10.15479/AT:ISTA:19885.
mla: Saez Mollejo, Jaime. Automated All-RF Tuning for Spin Qubit Readout and
Control. Institute of Science and Technology Austria, 2025, doi:10.15479/AT:ISTA:19885.
short: J. Saez Mollejo, (2025).
contributor:
- contributor_type: researcher
first_name: Cornelius
last_name: Carlsson
- contributor_type: researcher
first_name: 'Federico '
last_name: Fedele
- contributor_type: researcher
first_name: Stefano
last_name: Calcaterra
- contributor_type: researcher
first_name: ' Daniel '
last_name: Chrastina
- contributor_type: researcher
first_name: 'Giovanni '
last_name: Isella
- contributor_type: researcher
first_name: Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
- contributor_type: researcher
first_name: Natalia
last_name: Ares
corr_author: '1'
date_created: 2025-06-24T06:56:03Z
date_published: 2025-06-01T00:00:00Z
date_updated: 2025-07-01T07:19:26Z
day: '01'
ddc:
- '530'
department:
- _id: GradSch
- _id: GeKa
doi: 10.15479/AT:ISTA:19885
file:
- access_level: open_access
checksum: eff1ae9e46599fdfab8da00a2ca3c289
content_type: application/x-zip-compressed
creator: jsaezmol
date_created: 2025-06-24T15:14:13Z
date_updated: 2025-06-24T15:14:13Z
file_id: '19893'
file_name: DatasetsPaper.zip
file_size: 3404814792
relation: main_file
success: 1
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checksum: 21840ceac04d677a799b8e5bd919804f
content_type: text/plain
creator: jsaezmol
date_created: 2025-06-25T07:11:52Z
date_updated: 2025-06-25T07:11:52Z
file_id: '19899'
file_name: README.txt
file_size: 622
relation: main_file
success: 1
file_date_updated: 2025-06-25T07:11:52Z
has_accepted_license: '1'
month: '06'
oa: 1
oa_version: Published Version
project:
- _id: 34c0acea-11ca-11ed-8bc3-8775e10fd452
grant_number: '101069515'
name: Integrated Germanium Quantum Technology
- _id: c0977eea-5a5b-11eb-8a69-a862db0cf4d1
grant_number: I05060
name: High impedance circuit quantum electrodynamics with hole spins
- _id: 34a66131-11ca-11ed-8bc3-a31681c6b03e
grant_number: F8606
name: 'Center for Correlated Quantum Materials and Solid State Quantum Systems:
Conventional and unconventional topological superconductors'
publisher: Institute of Science and Technology Austria
status: public
title: Automated All-RF Tuning for Spin Qubit Readout and Control
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: research_data
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2025'
...
---
OA_place: publisher
OA_type: hybrid
PlanS_conform: '1'
_id: '20706'
abstract:
- lang: eng
text: We experimentally realize a quantum clock by using a charge sensor to count
charges tunneling through a double quantum dot (DQD). Individual tunneling events
are used as the clock’s ticks. We quantify the clock’s precision while measuring
the power dissipated by the DQD and, separately, the charge sensor in both direct-current
and radio-frequency readout modes. This allows us to probe the thermodynamic cost
of creating ticks microscopically and recording them macroscopically. Our experiment
is the first to explore the interplay between the entropy produced by a microscopic
clockwork and its macroscopic measurement apparatus. We show that the latter contribution
not only dwarfs the former but also unlocks greatly increased precision, because
the measurement record can be exploited to optimally estimate time even when the
DQD is at equilibrium. Our results suggest that the entropy produced by the amplification
and measurement of a clock’s ticks, which has often been ignored in the literature,
is the most important and fundamental thermodynamic cost of timekeeping at the
quantum scale.
acknowledgement: The authors thank Georgios Katsaros for providing the device for
this experiment, and Tony Apollaro, Ilia Khomchenko, and Gerard Milburn for discussions.
V. W. acknowledges funding from UK Research and Innovation Grant No. EP/T517811/1.
F. M., M. H., and P. E. acknowledge funding from the European Research Council (Consolidator
Grant “Cocoquest” No. 101043705). M. H. and P. E. acknowledge funding from the Austrian
Federal Ministry of Education, Science, and Research via the Austrian Research Promotion
Agency (FFG) through Quantum Austria. R. S. acknowledges funding from the Swiss
National Science Foundation via an Ambizione Grant No. PZ00P2_185986. M. T. M. is
supported by a Royal Society University Research Fellowship. N. A. acknowledges
support from the European Research Council (Grant Agreement No, 948932) and the
Royal Society (No. URF-R1-191150). This project is cofunded by the European Union
(Quantum Flagship project ASPECTS, Grant Agreement No. 101080167) and UK Research
and Innovation (UKRI). Views and opinions expressed are however those of the authors
only and do not necessarily reflect those of the European Union, Research Executive
Agency, or UKRI. Neither the European Union nor UKRI can be held responsible for
them.
article_number: '200407'
article_processing_charge: Yes (in subscription journal)
article_type: original
arxiv: 1
author:
- first_name: Vivek
full_name: Wadhia, Vivek
last_name: Wadhia
- first_name: Florian
full_name: Meier, Florian
last_name: Meier
- first_name: Federico
full_name: Fedele, Federico
last_name: Fedele
- first_name: Ralph
full_name: Silva, Ralph
last_name: Silva
- first_name: Nuriya
full_name: Nurgalieva, Nuriya
last_name: Nurgalieva
- first_name: David L.
full_name: Craig, David L.
last_name: Craig
- first_name: Daniel
full_name: Jirovec, Daniel
id: 4C473F58-F248-11E8-B48F-1D18A9856A87
last_name: Jirovec
orcid: 0000-0002-7197-4801
- first_name: Jaime
full_name: Saez Mollejo, Jaime
id: e0390f72-f6e0-11ea-865d-862393336714
last_name: Saez Mollejo
- first_name: Andrea
full_name: Ballabio, Andrea
last_name: Ballabio
- first_name: Daniel
full_name: Chrastina, Daniel
last_name: Chrastina
- first_name: Giovanni
full_name: Isella, Giovanni
last_name: Isella
- first_name: Marcus
full_name: Huber, Marcus
last_name: Huber
- first_name: Mark T.
full_name: Mitchison, Mark T.
last_name: Mitchison
- first_name: Paul
full_name: Erker, Paul
last_name: Erker
- first_name: Natalia
full_name: Ares, Natalia
last_name: Ares
citation:
ama: Wadhia V, Meier F, Fedele F, et al. Entropic costs of extracting classical
ticks from a quantum clock. Physical Review Letters. 2025;135(20). doi:10.1103/5rtj-djfk
apa: Wadhia, V., Meier, F., Fedele, F., Silva, R., Nurgalieva, N., Craig, D. L.,
… Ares, N. (2025). Entropic costs of extracting classical ticks from a quantum
clock. Physical Review Letters. American Physical Society. https://doi.org/10.1103/5rtj-djfk
chicago: Wadhia, Vivek, Florian Meier, Federico Fedele, Ralph Silva, Nuriya Nurgalieva,
David L. Craig, Daniel Jirovec, et al. “Entropic Costs of Extracting Classical
Ticks from a Quantum Clock.” Physical Review Letters. American Physical
Society, 2025. https://doi.org/10.1103/5rtj-djfk.
ieee: V. Wadhia et al., “Entropic costs of extracting classical ticks from
a quantum clock,” Physical Review Letters, vol. 135, no. 20. American Physical
Society, 2025.
ista: Wadhia V, Meier F, Fedele F, Silva R, Nurgalieva N, Craig DL, Jirovec D, Saez
Mollejo J, Ballabio A, Chrastina D, Isella G, Huber M, Mitchison MT, Erker P,
Ares N. 2025. Entropic costs of extracting classical ticks from a quantum clock.
Physical Review Letters. 135(20), 200407.
mla: Wadhia, Vivek, et al. “Entropic Costs of Extracting Classical Ticks from a
Quantum Clock.” Physical Review Letters, vol. 135, no. 20, 200407, American
Physical Society, 2025, doi:10.1103/5rtj-djfk.
short: V. Wadhia, F. Meier, F. Fedele, R. Silva, N. Nurgalieva, D.L. Craig, D. Jirovec,
J. Saez Mollejo, A. Ballabio, D. Chrastina, G. Isella, M. Huber, M.T. Mitchison,
P. Erker, N. Ares, Physical Review Letters 135 (2025).
date_created: 2025-11-30T23:02:07Z
date_published: 2025-11-14T00:00:00Z
date_updated: 2025-12-01T15:39:14Z
day: '14'
ddc:
- '530'
department:
- _id: GeKa
doi: 10.1103/5rtj-djfk
external_id:
arxiv:
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isi:
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publisher: American Physical Society
quality_controlled: '1'
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title: Entropic costs of extracting classical ticks from a quantum clock
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
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volume: 135
year: '2025'
...
---
APC_amount: 7068 EUR
DOAJ_listed: '1'
OA_place: publisher
OA_type: gold
_id: '19424'
abstract:
- lang: eng
text: "Hole spin qubits are rapidly emerging as the workhorse of semiconducting
quantum processors because of their large spin-orbit interaction, enabling fast
all-electric operations at low power. However, spin-orbit interaction also causes
non-uniformities in devices, resulting in locally varying qubit energies and site-dependent
anisotropies. While these anisotropies can be used to drive single-spins, if not
properly harnessed, they can hinder the path toward large-scale quantum processors.
Here, we report on microwave-driven singlet-triplet qubits in planar germanium
and use them to investigate the anisotropy of two spins in a double quantum dot.
We show two distinct operating regimes depending on the magnetic field direction.
For in-plane fields, the two spins are largely anisotropic, and electrically tunable,
which enables to measure all the available transitions; coherence times exceeding
3 $\\mu$s are extracted. For out-of-plane fields, they have an isotropic response
but preserve the substantial energy difference required to address the singlet-triplet
qubit. Even in this field direction, where the qubit lifetime\r\nis strongly affected
by nuclear spins, we find 400 ns coherence times. Our work adds a valuable tool
to investigate and harness the anisotropy of spin qubits and can be implemented
in any large-scale NxN device, facilitating the path towards scalable quantum
processors."
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: "We thank A. Crippa for helpful discussions. This research was supported
by the Scientific Service Units of ISTA through resources provided by the MIBA Machine
Shop and the Nanofabrication facility. This research and related results were made
possible with the support of the NOMIS Foundation, the HORIZON-RIA 101069515 project
and the FWF Projects with DOI:10.55776/F86 and DOI:10.55776/I5060. M.R.-R. acknowledges
support from the Netherlands Organization of Scientific Research (NWO) under Veni
grant VI.Veni.212.223. The\r\nResearch of S.B. and M.R.-R. was sponsored in part
by the Army Research Office and was accomplished under Award Number: W911NF-23-1-0110.
The views and conclusions contained in this document are those of the authors and
should not be interpreted as representing the official policies, either expressed
or implied, of the Army Research Office or the U.S. Government. The U.S. Government
is authorized to reproduce and distribute reprints for Government purposes notwithstanding
any copyright notation herein."
article_number: '3862'
article_processing_charge: Yes
article_type: original
arxiv: 1
author:
- first_name: Jaime
full_name: Saez Mollejo, Jaime
id: e0390f72-f6e0-11ea-865d-862393336714
last_name: Saez Mollejo
- first_name: Daniel
full_name: Jirovec, Daniel
id: 4C473F58-F248-11E8-B48F-1D18A9856A87
last_name: Jirovec
orcid: 0000-0002-7197-4801
- first_name: Yona A
full_name: Schell, Yona A
id: fe39122d-06bb-11ec-a33b-9e22b40e40a5
last_name: Schell
- first_name: Josip
full_name: Kukucka, Josip
id: 3F5D8856-F248-11E8-B48F-1D18A9856A87
last_name: Kukucka
- first_name: Stefano
full_name: Calcaterra, Stefano
last_name: Calcaterra
- first_name: Daniel
full_name: Chrastina, Daniel
last_name: Chrastina
- first_name: Giovanni
full_name: Isella, Giovanni
last_name: Isella
- first_name: Maximilian
full_name: Rimbach-Russ, Maximilian
last_name: Rimbach-Russ
- first_name: Stefano
full_name: Bosco, Stefano
last_name: Bosco
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
citation:
ama: Saez Mollejo J, Jirovec D, Schell YA, et al. Exchange anisotropies in microwave-driven
singlet-triplet qubits. Nature Communications. 2025;16. doi:10.1038/s41467-025-58969-y
apa: Saez Mollejo, J., Jirovec, D., Schell, Y. A., Kukucka, J., Calcaterra, S.,
Chrastina, D., … Katsaros, G. (2025). Exchange anisotropies in microwave-driven
singlet-triplet qubits. Nature Communications. Springer Nature. https://doi.org/10.1038/s41467-025-58969-y
chicago: Saez Mollejo, Jaime, Daniel Jirovec, Yona A Schell, Josip Kukucka, Stefano
Calcaterra, Daniel Chrastina, Giovanni Isella, Maximilian Rimbach-Russ, Stefano
Bosco, and Georgios Katsaros. “Exchange Anisotropies in Microwave-Driven Singlet-Triplet
Qubits.” Nature Communications. Springer Nature, 2025. https://doi.org/10.1038/s41467-025-58969-y.
ieee: J. Saez Mollejo et al., “Exchange anisotropies in microwave-driven
singlet-triplet qubits,” Nature Communications, vol. 16. Springer Nature,
2025.
ista: Saez Mollejo J, Jirovec D, Schell YA, Kukucka J, Calcaterra S, Chrastina D,
Isella G, Rimbach-Russ M, Bosco S, Katsaros G. 2025. Exchange anisotropies in
microwave-driven singlet-triplet qubits. Nature Communications. 16, 3862.
mla: Saez Mollejo, Jaime, et al. “Exchange Anisotropies in Microwave-Driven Singlet-Triplet
Qubits.” Nature Communications, vol. 16, 3862, Springer Nature, 2025, doi:10.1038/s41467-025-58969-y.
short: J. Saez Mollejo, D. Jirovec, Y.A. Schell, J. Kukucka, S. Calcaterra, D. Chrastina,
G. Isella, M. Rimbach-Russ, S. Bosco, G. Katsaros, Nature Communications 16 (2025).
corr_author: '1'
date_created: 2025-03-19T13:28:12Z
date_published: 2025-04-24T00:00:00Z
date_updated: 2026-08-05T22:31:11Z
day: '24'
ddc:
- '530'
department:
- _id: GeKa
doi: 10.1038/s41467-025-58969-y
external_id:
arxiv:
- '2408.03224'
isi:
- '001475587400022'
pmid:
- '40274808'
file:
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checksum: 13fe84cddc9d4e47213bf17acdac70d7
content_type: application/pdf
creator: dernst
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has_accepted_license: '1'
intvolume: ' 16'
isi: 1
language:
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month: '04'
oa: 1
oa_version: Published Version
pmid: 1
project:
- _id: 34c0acea-11ca-11ed-8bc3-8775e10fd452
grant_number: '101069515'
name: Integrated Germanium Quantum Technology
- _id: 34a66131-11ca-11ed-8bc3-a31681c6b03e
grant_number: F8606
name: 'Center for Correlated Quantum Materials and Solid State Quantum Systems:
Conventional and unconventional topological superconductors'
- _id: c0977eea-5a5b-11eb-8a69-a862db0cf4d1
grant_number: I05060
name: High impedance circuit quantum electrodynamics with hole spins
- _id: 262116AA-B435-11E9-9278-68D0E5697425
name: Hybrid Semiconductor - Superconductor Quantum Devices
- _id: 3AC91DDA-15DF-11EA-824D-93A3E7B544D1
call_identifier: FWF
name: FWF Open Access Fund
publication: Nature Communications
publication_identifier:
eissn:
- 2041-1723
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
link:
- description: News on ISTA website
relation: research_data
url: https://ista.ac.at/en/news/the-shadow-of-an-electron/
record:
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relation: research_data
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relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Exchange anisotropies in microwave-driven singlet-triplet 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: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 16
year: '2025'
...
---
OA_place: publisher
_id: '19836'
abstract:
- lang: eng
text: "Over the past century, researchers have been fascinated by the quantum nature
of the\r\nphysical world, initially striving to understand its fundamental principles
and consequences, and\r\neventually progressing toward engineering systems that
can control and manipulate quantum\r\nproperties. Today, we stand at the dawn
of the quantum technology era. While some quantum\r\ntechnologies follow well-defined
roadmaps, others are still in the exciting and uncertain early\r\nstages of development.
In the fields of quantum computing and quantum simulation, research\r\nis being
conducted across a wide variety of platforms. Each of these demonstrates control
over\r\nquantum properties but also faces challenges in scaling up to the level
of a mature technology.\r\nThis thesis explores some of the fundamental properties
of hole spin qubits in planar germanium.\r\nSemiconductor spin qubits are considered
strong candidates for the realization of quantum\r\nprocessors, owing to their
long relaxation and coherence times, as well as their compatibility\r\nwith existing
semiconductor industry infrastructure. Among these, hole spin qubits in planar\r\ngermanium
are particularly promising. Their advantages include a large effective mass, which\r\neases
fabrication constraints; inherent protection from hyperfine noise; and strong
spin-orbit\r\ninteraction, which enables fast and purely electrical control. However,
spin-orbit coupling also\r\nintroduces site-dependent variability across qubits,
particularly in the g-tensors and spin-flip\r\ntunneling, which might cause that
the quantization axes are not aligned. In this thesis, we\r\ninvestigate the tilt
between the quantization axes of two hole spins hosted in a double quantum\r\ndot
as a function of both the magnetic field direction and various electrostatic configurations,\r\ndemonstrating
that both parameters influence this tilt. We conclude by introducing a machine-learning-assisted
routine to automatically tune baseband spin qubits. This approach may prove\r\nto
be a powerful tool for characterizing spin-orbit effects and gaining deeper insight
into the\r\nphysics governing spin qubit behavior.\r\n"
acknowledged_ssus:
- _id: NanoFab
- _id: M-Shop
acknowledgement: "This research was supported by the Scientific Service Units of ISTA
through resources provided\r\nby the MIBA Machine Shop and the Nanofabrication facility.
We acknowledge the support from\r\nthe European Commission with the project Integrated
Germanium Quantum Technology (with\r\nDOI:10.3030/101069515), the NOMIS Foundation,
the HORIZON-RIA 101069515 project and\r\nthe FWF Projects Center for Correlated
Quantum Materials and Solid State Quantum Systems:\r\nConventional and unconventional
topological superconductors (with DOI:10.55776/F86) and\r\nHigh impedance circuit
quantum electrodynamics with hole spins (with DOI:10.55776/I5060).\r\n"
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Jaime
full_name: Saez Mollejo, Jaime
id: e0390f72-f6e0-11ea-865d-862393336714
last_name: Saez Mollejo
citation:
ama: 'Saez Mollejo J. Singlet-triplet qubits in planar Germanium: From exchange
anisotropies to autonomous tuning . 2025. doi:10.15479/AT-ISTA-19836'
apa: 'Saez Mollejo, J. (2025). Singlet-triplet qubits in planar Germanium: From
exchange anisotropies to autonomous tuning . Institute of Science and Technology
Austria. https://doi.org/10.15479/AT-ISTA-19836'
chicago: 'Saez Mollejo, Jaime. “Singlet-Triplet Qubits in Planar Germanium: From
Exchange Anisotropies to Autonomous Tuning .” Institute of Science and Technology
Austria, 2025. https://doi.org/10.15479/AT-ISTA-19836.'
ieee: 'J. Saez Mollejo, “Singlet-triplet qubits in planar Germanium: From exchange
anisotropies to autonomous tuning ,” Institute of Science and Technology Austria,
2025.'
ista: 'Saez Mollejo J. 2025. Singlet-triplet qubits in planar Germanium: From exchange
anisotropies to autonomous tuning . Institute of Science and Technology Austria.'
mla: 'Saez Mollejo, Jaime. Singlet-Triplet Qubits in Planar Germanium: From Exchange
Anisotropies to Autonomous Tuning . Institute of Science and Technology Austria,
2025, doi:10.15479/AT-ISTA-19836.'
short: 'J. Saez Mollejo, Singlet-Triplet Qubits in Planar Germanium: From Exchange
Anisotropies to Autonomous Tuning , Institute of Science and Technology Austria,
2025.'
corr_author: '1'
date_created: 2025-06-13T09:01:50Z
date_published: 2025-06-13T00:00:00Z
date_updated: 2026-07-29T12:55:59Z
day: '13'
ddc:
- '530'
- '539'
degree_awarded: PhD
department:
- _id: GradSch
- _id: GeKa
doi: 10.15479/AT-ISTA-19836
doi_confirm: '1'
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file_date_updated: 2026-04-01T22:30:07Z
has_accepted_license: '1'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
page: '175'
project:
- _id: 34c0acea-11ca-11ed-8bc3-8775e10fd452
grant_number: '101069515'
name: Integrated Germanium Quantum Technology
- _id: 34a66131-11ca-11ed-8bc3-a31681c6b03e
grant_number: F8606
name: 'Center for Correlated Quantum Materials and Solid State Quantum Systems:
Conventional and unconventional topological superconductors'
- _id: c0977eea-5a5b-11eb-8a69-a862db0cf4d1
grant_number: I05060
name: High impedance circuit quantum electrodynamics with hole spins
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '19424'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
title: 'Singlet-triplet qubits in planar Germanium: From exchange anisotropies to
autonomous tuning '
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: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2025'
...
---
_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
orcid: 0000-0001-5263-5559
- 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
orcid: 0009-0005-0878-3032
- 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.
corr_author: '1'
date_created: 2023-08-11T07:41:17Z
date_published: 2023-11-01T00:00:00Z
date_updated: 2026-08-05T22:30:19Z
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:
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checksum: 1fc86d71bfbf836e221c1e925343adc5
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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
publication: Nature Physics
publication_identifier:
eissn:
- 1745-2481
issn:
- 1745-2473
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
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relation: dissertation_contains
status: public
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'
...
---
_id: '8909'
abstract:
- lang: eng
text: Spin qubits are considered to be among the most promising candidates for building
a quantum processor. Group IV hole spin qubits have moved into the focus of interest
due to the ease of operation and compatibility with Si technology. In addition,
Ge offers the option for monolithic superconductor-semiconductor integration.
Here we demonstrate a hole spin qubit operating at fields below 10 mT, the critical
field of Al, by exploiting the large out-of-plane hole g-factors in planar Ge
and by encoding the qubit into the singlet-triplet states of a double quantum
dot. We observe electrically controlled X and Z-rotations with tunable frequencies
exceeding 100 MHz and dephasing times of 1μs which we extend beyond 15μs with
echo techniques. These results show that Ge hole singlet triplet qubits outperform
their electronic Si and GaAs based counterparts in speed and coherence, respectively.
In addition, they are on par with Ge single spin qubits, but can be operated at
much lower fields underlining their potential for on chip integration with superconducting
technologies.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: This research was supported by the Scientific Service Units of Institute
of Science and Technology (IST) Austria through resources provided by the Miba Machine
Shop and the nanofabrication facility, and was made possible with the support of
the NOMIS Foundation. This project has received funding from the European Union’s
Horizon 2020 research and innovation programme under Marie Sklodowska-Curie grant
agreements no. 844511 and no. 75441, and by the Austrian Science Fund FWF-P 30207
project. A.B. acknowledges support from the European Union Horizon 2020 FET project
microSPIRE, no. 766955. M. Botifoll and J.A. acknowledge funding from Generalitat
de Catalunya 2017 SGR 327. The Catalan Institute of Nanoscience and Nanotechnology
(ICN2) is supported by the Severo Ochoa programme from the Spanish Ministery of
Economy (MINECO) (grant no. SEV-2017-0706) and is funded by the Catalonian Research
Centre (CERCA) Programme, Generalitat de Catalunya. Part of the present work has
been performed within the framework of the Universitat Autónoma de Barcelona Materials
Science PhD programme. Part of the HAADF scanning transmission electron microscopy
was conducted in the Laboratorio de Microscopias Avanzadas at Instituto de Nanociencia
de Aragon, Universidad de Zaragoza. ICN2 acknowledge support from the Spanish Superior
Council of Scientific Research (CSIC) Research Platform on Quantum Technologies
PTI-001. M.B. acknowledges funding from the Catalan Agency for Management of University
and Research Grants (AGAUR) Generalitat de Catalunya formation of investigators
(FI) PhD grant.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Daniel
full_name: Jirovec, Daniel
id: 4C473F58-F248-11E8-B48F-1D18A9856A87
last_name: Jirovec
orcid: 0000-0002-7197-4801
- first_name: Andrea C
full_name: Hofmann, Andrea C
id: 340F461A-F248-11E8-B48F-1D18A9856A87
last_name: Hofmann
- first_name: Andrea
full_name: Ballabio, Andrea
last_name: Ballabio
- first_name: Philipp M.
full_name: Mutter, Philipp M.
last_name: Mutter
- first_name: Giulio
full_name: Tavani, Giulio
last_name: Tavani
- first_name: Marc
full_name: Botifoll, Marc
last_name: Botifoll
- first_name: Alessandro
full_name: Crippa, Alessandro
id: 1F2B21A2-F6E7-11E9-9B82-F7DBE5697425
last_name: Crippa
orcid: 0000-0002-2968-611X
- first_name: Josip
full_name: Kukucka, Josip
id: 3F5D8856-F248-11E8-B48F-1D18A9856A87
last_name: Kukucka
- first_name: Oliver
full_name: Sagi, Oliver
id: 71616374-A8E9-11E9-A7CA-09ECE5697425
last_name: Sagi
- first_name: Frederico
full_name: Martins, Frederico
id: 38F80F9A-1CB8-11EA-BC76-B49B3DDC885E
last_name: Martins
orcid: 0000-0003-2668-2401
- first_name: Jaime
full_name: Saez Mollejo, Jaime
id: e0390f72-f6e0-11ea-865d-862393336714
last_name: Saez Mollejo
- first_name: Ivan
full_name: Prieto Gonzalez, Ivan
id: 2A307FE2-F248-11E8-B48F-1D18A9856A87
last_name: Prieto Gonzalez
orcid: 0000-0002-7370-5357
- first_name: Maksim
full_name: Borovkov, Maksim
id: 2ac7a0a2-3562-11eb-9256-fbd18ea55087
last_name: Borovkov
- first_name: Jordi
full_name: Arbiol, Jordi
last_name: Arbiol
- first_name: Daniel
full_name: Chrastina, Daniel
last_name: Chrastina
- first_name: Giovanni
full_name: Isella, Giovanni
last_name: Isella
- first_name: Georgios
full_name: Katsaros, Georgios
id: 38DB5788-F248-11E8-B48F-1D18A9856A87
last_name: Katsaros
orcid: 0000-0001-8342-202X
citation:
ama: Jirovec D, Hofmann AC, Ballabio A, et al. A singlet triplet hole spin qubit
in planar Ge. Nature Materials. 2021;20(8):1106–1112. doi:10.1038/s41563-021-01022-2
apa: Jirovec, D., Hofmann, A. C., Ballabio, A., Mutter, P. M., Tavani, G., Botifoll,
M., … Katsaros, G. (2021). A singlet triplet hole spin qubit in planar Ge. Nature
Materials. Springer Nature. https://doi.org/10.1038/s41563-021-01022-2
chicago: Jirovec, Daniel, Andrea C Hofmann, Andrea Ballabio, Philipp M. Mutter,
Giulio Tavani, Marc Botifoll, Alessandro Crippa, et al. “A Singlet Triplet Hole
Spin Qubit in Planar Ge.” Nature Materials. Springer Nature, 2021. https://doi.org/10.1038/s41563-021-01022-2.
ieee: D. Jirovec et al., “A singlet triplet hole spin qubit in planar Ge,”
Nature Materials, vol. 20, no. 8. Springer Nature, pp. 1106–1112, 2021.
ista: Jirovec D, Hofmann AC, Ballabio A, Mutter PM, Tavani G, Botifoll M, Crippa
A, Kukucka J, Sagi O, Martins F, Saez Mollejo J, Prieto Gonzalez I, Borovkov M,
Arbiol J, Chrastina D, Isella G, Katsaros G. 2021. A singlet triplet hole spin
qubit in planar Ge. Nature Materials. 20(8), 1106–1112.
mla: Jirovec, Daniel, et al. “A Singlet Triplet Hole Spin Qubit in Planar Ge.” Nature
Materials, vol. 20, no. 8, Springer Nature, 2021, pp. 1106–1112, doi:10.1038/s41563-021-01022-2.
short: D. Jirovec, A.C. Hofmann, A. Ballabio, P.M. Mutter, G. Tavani, M. Botifoll,
A. Crippa, J. Kukucka, O. Sagi, F. Martins, J. Saez Mollejo, I. Prieto Gonzalez,
M. Borovkov, J. Arbiol, D. Chrastina, G. Isella, G. Katsaros, Nature Materials
20 (2021) 1106–1112.
corr_author: '1'
date_created: 2020-12-02T10:50:47Z
date_published: 2021-08-01T00:00:00Z
date_updated: 2026-08-05T22:30:49Z
day: '01'
department:
- _id: GeKa
- _id: NanoFab
- _id: GradSch
doi: 10.1038/s41563-021-01022-2
ec_funded: 1
external_id:
arxiv:
- '2011.13755'
isi:
- '000657596400001'
pmid:
- '34083775'
intvolume: ' 20'
isi: 1
issue: '8'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2011.13755
month: '08'
oa: 1
oa_version: Preprint
page: 1106–1112
pmid: 1
project:
- _id: 26A151DA-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '844511'
name: Majorana bound states in Ge/SiGe heterostructures
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
- _id: 2641CE5E-B435-11E9-9278-68D0E5697425
call_identifier: FWF
grant_number: P30207
name: Hole spin orbit qubits in Ge quantum wells
- _id: 262116AA-B435-11E9-9278-68D0E5697425
name: Hybrid Semiconductor - Superconductor Quantum Devices
publication: Nature Materials
publication_identifier:
eissn:
- 1476-4660
issn:
- 1476-1122
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
link:
- description: News on IST Homepage
relation: press_release
url: https://ist.ac.at/en/news/quantum-computing-with-holes/
record:
- id: '9323'
relation: research_data
status: public
- id: '10058'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: A singlet triplet hole spin qubit in planar Ge
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 20
year: '2021'
...