---
_id: '10920'
abstract:
- lang: eng
  text: The spin-orbit interaction permits to control the state of a spin qubit via
    electric fields. For holes it is particularly strong, allowing for fast all electrical
    qubit manipulation, and yet an in-depth understanding of this interaction in hole
    systems is missing. Here we investigate, experimentally and theoretically, the
    effect of the cubic Rashba spin-orbit interaction on the mixing of the spin states
    by studying singlet-triplet oscillations in a planar Ge hole double quantum dot.
    Landau-Zener sweeps at different magnetic field directions allow us to disentangle
    the effects of the spin-orbit induced spin-flip term from those caused by strongly
    site-dependent and anisotropic quantum dot g tensors. Our work, therefore, provides
    new insights into the hole spin-orbit interaction, necessary for optimizing future
    qubit experiments.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: "This research was supported by the Scientific Service Units of ISTA
  through resources provided by the MIBA Machine Shop and the nanofabrication facility.
  This project has received funding from the European Union’s Horizon 2020 research
  and innovation program under the Marie\r\nSkłodowska-Curie Grant Agreement No. 844511,
  No. 75441, and by the FWF-P 30207, I05060, and M3032-N projects. A. B. acknowledges
  support from the EU Horizon-2020 FET project microSPIRE, ID: 766955. P.M. M. and
  G. B. acknowledge funding by the Deutsche Forschungsgemeinschaft (DFG—German Research
  Foundation) under Project No. 450396347. This work was supported by the Royal Society
  (URF\\R1\\191150) and the European Research Council (Grant Agreement No. 948932),
  N. A. acknowledges the use of the University of Oxford Advanced Research Computing
  (ARC) facility."
article_number: '126803'
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: Philipp M.
  full_name: Mutter, Philipp M.
  last_name: Mutter
- first_name: Andrea C
  full_name: Hofmann, Andrea C
  id: 340F461A-F248-11E8-B48F-1D18A9856A87
  last_name: Hofmann
- first_name: Alessandro
  full_name: Crippa, Alessandro
  id: 1F2B21A2-F6E7-11E9-9B82-F7DBE5697425
  last_name: Crippa
  orcid: 0000-0002-2968-611X
- first_name: Marek
  full_name: Rychetsky, Marek
  last_name: Rychetsky
- first_name: David L.
  full_name: Craig, David L.
  last_name: Craig
- first_name: Josip
  full_name: Kukucka, Josip
  id: 3F5D8856-F248-11E8-B48F-1D18A9856A87
  last_name: Kukucka
- first_name: Frederico
  full_name: Martins, Frederico
  id: 38F80F9A-1CB8-11EA-BC76-B49B3DDC885E
  last_name: Martins
  orcid: 0000-0003-2668-2401
- first_name: Andrea
  full_name: Ballabio, Andrea
  last_name: Ballabio
- first_name: Natalia
  full_name: Ares, Natalia
  last_name: Ares
- first_name: Daniel
  full_name: Chrastina, Daniel
  last_name: Chrastina
- first_name: Giovanni
  full_name: Isella, Giovanni
  last_name: Isella
- first_name: 'Guido '
  full_name: 'Burkard, Guido '
  last_name: Burkard
- first_name: Georgios
  full_name: Katsaros, Georgios
  id: 38DB5788-F248-11E8-B48F-1D18A9856A87
  last_name: Katsaros
citation:
  ama: Jirovec D, Mutter PM, Hofmann AC, et al. Dynamics of hole singlet-triplet qubits
    with large g-factor differences. <i>Physical Review Letters</i>. 2022;128(12).
    doi:<a href="https://doi.org/10.1103/PhysRevLett.128.126803">10.1103/PhysRevLett.128.126803</a>
  apa: Jirovec, D., Mutter, P. M., Hofmann, A. C., Crippa, A., Rychetsky, M., Craig,
    D. L., … Katsaros, G. (2022). Dynamics of hole singlet-triplet qubits with large
    g-factor differences. <i>Physical Review Letters</i>. American Physical Society.
    <a href="https://doi.org/10.1103/PhysRevLett.128.126803">https://doi.org/10.1103/PhysRevLett.128.126803</a>
  chicago: Jirovec, Daniel, Philipp M. Mutter, Andrea C Hofmann, Alessandro Crippa,
    Marek Rychetsky, David L. Craig, Josip Kukucka, et al. “Dynamics of Hole Singlet-Triplet
    Qubits with Large g-Factor Differences.” <i>Physical Review Letters</i>. American
    Physical Society, 2022. <a href="https://doi.org/10.1103/PhysRevLett.128.126803">https://doi.org/10.1103/PhysRevLett.128.126803</a>.
  ieee: D. Jirovec <i>et al.</i>, “Dynamics of hole singlet-triplet qubits with large
    g-factor differences,” <i>Physical Review Letters</i>, vol. 128, no. 12. American
    Physical Society, 2022.
  ista: Jirovec D, Mutter PM, Hofmann AC, Crippa A, Rychetsky M, Craig DL, Kukucka
    J, Martins F, Ballabio A, Ares N, Chrastina D, Isella G, Burkard G, Katsaros G.
    2022. Dynamics of hole singlet-triplet qubits with large g-factor differences.
    Physical Review Letters. 128(12), 126803.
  mla: Jirovec, Daniel, et al. “Dynamics of Hole Singlet-Triplet Qubits with Large
    g-Factor Differences.” <i>Physical Review Letters</i>, vol. 128, no. 12, 126803,
    American Physical Society, 2022, doi:<a href="https://doi.org/10.1103/PhysRevLett.128.126803">10.1103/PhysRevLett.128.126803</a>.
  short: D. Jirovec, P.M. Mutter, A.C. Hofmann, A. Crippa, M. Rychetsky, D.L. Craig,
    J. Kukucka, F. Martins, A. Ballabio, N. Ares, D. Chrastina, G. Isella, G. Burkard,
    G. Katsaros, Physical Review Letters 128 (2022).
date_created: 2022-03-24T15:51:11Z
date_published: 2022-03-24T00:00:00Z
date_updated: 2023-08-03T06:14:58Z
day: '24'
ddc:
- '530'
department:
- _id: GradSch
- _id: GeKa
doi: 10.1103/PhysRevLett.128.126803
ec_funded: 1
external_id:
  arxiv:
  - '2111.05130'
  isi:
  - '000786542500004'
file:
- access_level: open_access
  checksum: 6e66ad548d18db9c131f304acbd5a1f4
  content_type: application/pdf
  creator: dernst
  date_created: 2022-03-28T06:53:39Z
  date_updated: 2022-03-28T06:53:39Z
  file_id: '10928'
  file_name: 2022_PhysRevLetters_Jirovec.pdf
  file_size: 1266515
  relation: main_file
  success: 1
file_date_updated: 2022-03-28T06:53:39Z
has_accepted_license: '1'
intvolume: '       128'
isi: 1
issue: '12'
language:
- iso: eng
month: '03'
oa: 1
oa_version: Published Version
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: c0977eea-5a5b-11eb-8a69-a862db0cf4d1
  grant_number: I05060
  name: High impedance circuit quantum electrodynamics with hole spins
- _id: c08c05c4-5a5b-11eb-8a69-dc6ce49d7973
  grant_number: M03032
  name: Long-range spin exchange for 2D qubits architectures
publication: Physical Review Letters
publication_identifier:
  eissn:
  - 1079-7114
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: Dynamics of hole singlet-triplet qubits with large g-factor differences
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: 128
year: '2022'
...
---
_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. <i>Nature Materials</i>. 2021;20(8):1106–1112. doi:<a href="https://doi.org/10.1038/s41563-021-01022-2">10.1038/s41563-021-01022-2</a>
  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. <i>Nature
    Materials</i>. Springer Nature. <a href="https://doi.org/10.1038/s41563-021-01022-2">https://doi.org/10.1038/s41563-021-01022-2</a>
  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.” <i>Nature Materials</i>. Springer Nature, 2021. <a href="https://doi.org/10.1038/s41563-021-01022-2">https://doi.org/10.1038/s41563-021-01022-2</a>.
  ieee: D. Jirovec <i>et al.</i>, “A singlet triplet hole spin qubit in planar Ge,”
    <i>Nature Materials</i>, 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.” <i>Nature
    Materials</i>, vol. 20, no. 8, Springer Nature, 2021, pp. 1106–1112, doi:<a href="https://doi.org/10.1038/s41563-021-01022-2">10.1038/s41563-021-01022-2</a>.
  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.
date_created: 2020-12-02T10:50:47Z
date_published: 2021-08-01T00:00:00Z
date_updated: 2024-03-25T23:30:14Z
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'
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
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: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 20
year: '2021'
...
---
_id: '9323'
abstract:
- lang: eng
  text: This .zip File contains the data for figures presented in the main text and
    supplementary material of "A singlet triplet hole spin qubit in planar Ge" by
    D. Jirovec, et. al. The measurements were done using Labber Software and the data
    is stored in the hdf5 file format. The files can be opened using either the Labber
    Log Browser (https://labber.org/overview/) or Labber Python API (http://labber.org/online-doc/api/LogFile.html).
    A single file is acquired with QCodes and features the corresponding data type.
    XRD data are in .dat format and a code to open the data is provided. The code
    for simulations is as well provided in Python.
article_processing_charge: No
author:
- first_name: Daniel
  full_name: Jirovec, Daniel
  id: 4C473F58-F248-11E8-B48F-1D18A9856A87
  last_name: Jirovec
  orcid: 0000-0002-7197-4801
citation:
  ama: Jirovec D. Research data for “A singlet-triplet hole spin qubit planar Ge.”
    2021. doi:<a href="https://doi.org/10.15479/AT:ISTA:9323">10.15479/AT:ISTA:9323</a>
  apa: Jirovec, D. (2021). Research data for “A singlet-triplet hole spin qubit planar
    Ge.” Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:9323">https://doi.org/10.15479/AT:ISTA:9323</a>
  chicago: Jirovec, Daniel. “Research Data for ‘A Singlet-Triplet Hole Spin Qubit
    Planar Ge.’” Institute of Science and Technology Austria, 2021. <a href="https://doi.org/10.15479/AT:ISTA:9323">https://doi.org/10.15479/AT:ISTA:9323</a>.
  ieee: D. Jirovec, “Research data for ‘A singlet-triplet hole spin qubit planar Ge.’”
    Institute of Science and Technology Austria, 2021.
  ista: Jirovec D. 2021. Research data for ‘A singlet-triplet hole spin qubit planar
    Ge’, Institute of Science and Technology Austria, <a href="https://doi.org/10.15479/AT:ISTA:9323">10.15479/AT:ISTA:9323</a>.
  mla: Jirovec, Daniel. <i>Research Data for “A Singlet-Triplet Hole Spin Qubit Planar
    Ge.”</i> Institute of Science and Technology Austria, 2021, doi:<a href="https://doi.org/10.15479/AT:ISTA:9323">10.15479/AT:ISTA:9323</a>.
  short: D. Jirovec, (2021).
contributor:
- contributor_type: project_member
  first_name: Daniel
  id: 4C473F58-F248-11E8-B48F-1D18A9856A87
  last_name: Jirovec
date_created: 2021-04-14T09:50:22Z
date_published: 2021-04-14T00:00:00Z
date_updated: 2024-02-21T12:39:15Z
day: '14'
ddc:
- '530'
department:
- _id: GradSch
- _id: GeKa
doi: 10.15479/AT:ISTA:9323
file:
- access_level: open_access
  checksum: c569d2a2ce1694445cdbca19cf8ae023
  content_type: application/x-zip-compressed
  creator: djirovec
  date_created: 2021-04-14T09:48:47Z
  date_updated: 2021-04-14T09:48:47Z
  file_id: '9324'
  file_name: DataRepositorySTqubit.zip
  file_size: 221832287
  relation: main_file
  success: 1
- access_level: open_access
  checksum: 845bdf87430718ad6aff47eda7b5fc92
  content_type: application/octet-stream
  creator: djirovec
  date_created: 2021-04-14T09:49:30Z
  date_updated: 2021-04-14T09:49:30Z
  file_id: '9325'
  file_name: ReadMe
  file_size: 4323
  relation: main_file
  success: 1
file_date_updated: 2021-04-14T09:49:30Z
has_accepted_license: '1'
license: https://creativecommons.org/publicdomain/zero/1.0/
month: '04'
oa: 1
oa_version: Published Version
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '8909'
    relation: used_in_publication
    status: public
status: public
title: Research data for "A singlet-triplet hole spin qubit planar Ge"
tmp:
  image: /images/cc_0.png
  legal_code_url: https://creativecommons.org/publicdomain/zero/1.0/legalcode
  name: Creative Commons Public Domain Dedication (CC0 1.0)
  short: CC0 (1.0)
type: research_data
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2021'
...
---
_id: '10058'
abstract:
- lang: eng
  text: 'Quantum information and computation has become a vast field paved with opportunities
    for researchers and investors. As large multinational companies and international
    funds are heavily investing in quantum technologies it is still a question which
    platform is best suited for the task of realizing a scalable quantum processor.
    In this work we investigate hole spins in Ge quantum wells. These hold great promise
    as they possess several favorable properties: a small effective mass, a strong
    spin-orbit coupling, long relaxation time and an inherent immunity to hyperfine
    noise. All these characteristics helped Ge hole spin qubits to evolve from a single
    qubit to a fully entangled four qubit processor in only 3 years. Here, we investigated
    a qubit approach leveraging the large out-of-plane g-factors of heavy hole states
    in Ge quantum dots. We found this qubit to be reproducibly operable at extremely
    low magnetic field and at large speeds while maintaining coherence. This was possible
    because large differences of g-factors in adjacent dots can be achieved in the
    out-of-plane direction. In the in-plane direction the small g-factors, on the
    other hand, can be altered very effectively by the confinement potentials. Here,
    we found that this can even lead to a sign change of the g-factors. The resulting
    g-factor difference alters the dynamics of the system drastically and produces
    effects typically attributed to a spin-orbit induced spin-flip term.  The investigations
    carried out in this thesis give further insights into the possibilities of holes
    in Ge and reveal new physical properties that need to be considered when designing
    future spin qubit experiments.'
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: The author gratefully acknowledges support by the Austrian Science
  Fund (FWF), grants No P30207, and the Nomis foundation.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Daniel
  full_name: Jirovec, Daniel
  id: 4C473F58-F248-11E8-B48F-1D18A9856A87
  last_name: Jirovec
  orcid: 0000-0002-7197-4801
citation:
  ama: Jirovec D. Singlet-Triplet qubits and spin-orbit interaction in 2-dimensional
    Ge hole gases. 2021. doi:<a href="https://doi.org/10.15479/at:ista:10058">10.15479/at:ista:10058</a>
  apa: Jirovec, D. (2021). <i>Singlet-Triplet qubits and spin-orbit interaction in
    2-dimensional Ge hole gases</i>. Institute of Science and Technology Austria.
    <a href="https://doi.org/10.15479/at:ista:10058">https://doi.org/10.15479/at:ista:10058</a>
  chicago: Jirovec, Daniel. “Singlet-Triplet Qubits and Spin-Orbit Interaction in
    2-Dimensional Ge Hole Gases.” Institute of Science and Technology Austria, 2021.
    <a href="https://doi.org/10.15479/at:ista:10058">https://doi.org/10.15479/at:ista:10058</a>.
  ieee: D. Jirovec, “Singlet-Triplet qubits and spin-orbit interaction in 2-dimensional
    Ge hole gases,” Institute of Science and Technology Austria, 2021.
  ista: Jirovec D. 2021. Singlet-Triplet qubits and spin-orbit interaction in 2-dimensional
    Ge hole gases. Institute of Science and Technology Austria.
  mla: Jirovec, Daniel. <i>Singlet-Triplet Qubits and Spin-Orbit Interaction in 2-Dimensional
    Ge Hole Gases</i>. Institute of Science and Technology Austria, 2021, doi:<a href="https://doi.org/10.15479/at:ista:10058">10.15479/at:ista:10058</a>.
  short: D. Jirovec, Singlet-Triplet Qubits and Spin-Orbit Interaction in 2-Dimensional
    Ge Hole Gases, Institute of Science and Technology Austria, 2021.
date_created: 2021-09-30T07:53:49Z
date_published: 2021-10-05T00:00:00Z
date_updated: 2023-09-08T11:41:08Z
day: '05'
ddc:
- '621'
- '539'
degree_awarded: PhD
department:
- _id: GradSch
- _id: GeKa
doi: 10.15479/at:ista:10058
file:
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  file_size: 26910829
  relation: main_file
file_date_updated: 2022-12-20T23:30:07Z
has_accepted_license: '1'
keyword:
- qubits
- quantum computing
- holes
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
page: '151'
project:
- _id: 2641CE5E-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: P30207
  name: Hole spin orbit qubits in Ge quantum wells
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '8831'
    relation: part_of_dissertation
    status: public
  - id: '10065'
    relation: part_of_dissertation
    status: public
  - id: '10066'
    relation: part_of_dissertation
    status: public
  - id: '8909'
    relation: part_of_dissertation
    status: public
  - id: '5816'
    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 and spin-orbit interaction in 2-dimensional Ge hole
  gases
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2021'
...
---
_id: '10066'
abstract:
- lang: eng
  text: The potential of Si and SiGe-based devices for the scaling of quantum circuits
    is tainted by device variability. Each device needs to be tuned to operation conditions.
    We give a key step towards tackling this variability with an algorithm that, without
    modification, is capable of tuning a 4-gate Si FinFET, a 5-gate GeSi nanowire
    and a 7-gate SiGe heterostructure double quantum dot device from scratch. We achieve
    tuning times of 30, 10, and 92 minutes, respectively. The algorithm also provides
    insight into the parameter space landscape for each of these devices. These results
    show that overarching solutions for the tuning of quantum devices are enabled
    by machine learning.
acknowledged_ssus:
- _id: NanoFab
acknowledgement: "We acknowledge Ang Li, Erik P. A. M. Bakkers (University of Eindhoven)
  for the fabrication of the Ge/Si nanowire. This work was supported by the Royal
  Society, the EPSRC National Quantum Technology Hub in Networked Quantum Information
  Technology (EP/M013243/1), Quantum Technology Capital (EP/N014995/1), EPSRC Platform
  Grant\r\n(EP/R029229/1), the European Research Council (Grant agreement 948932),
  the Swiss Nanoscience Institute, the\r\nNCCR SPIN, the EU H2020 European Microkelvin
  Platform EMP grant No. 824109, the Scientific Service Units\r\nof IST Austria through
  resources provided by the nanofabrication facility and, the FWF-P30207 project.
  This publication was also made possible through support from Templeton World Charity
  Foundation and John Templeton Foundation. The opinions expressed in this publication
  are those of the authors and do not necessarily reflect the views of the Templeton
  Foundations."
article_number: '2107.12975'
article_processing_charge: No
arxiv: 1
author:
- first_name: B.
  full_name: Severin, B.
  last_name: Severin
- first_name: D. T.
  full_name: Lennon, D. T.
  last_name: Lennon
- first_name: L. C.
  full_name: Camenzind, L. C.
  last_name: Camenzind
- first_name: F.
  full_name: Vigneau, F.
  last_name: Vigneau
- first_name: F.
  full_name: Fedele, F.
  last_name: Fedele
- first_name: Daniel
  full_name: Jirovec, Daniel
  id: 4C473F58-F248-11E8-B48F-1D18A9856A87
  last_name: Jirovec
  orcid: 0000-0002-7197-4801
- first_name: A.
  full_name: Ballabio, A.
  last_name: Ballabio
- first_name: D.
  full_name: Chrastina, D.
  last_name: Chrastina
- first_name: G.
  full_name: Isella, G.
  last_name: Isella
- first_name: M. de
  full_name: Kruijf, M. de
  last_name: Kruijf
- first_name: M. J.
  full_name: Carballido, M. J.
  last_name: Carballido
- first_name: S.
  full_name: Svab, S.
  last_name: Svab
- first_name: A. V.
  full_name: Kuhlmann, A. V.
  last_name: Kuhlmann
- first_name: F. R.
  full_name: Braakman, F. R.
  last_name: Braakman
- first_name: S.
  full_name: Geyer, S.
  last_name: Geyer
- first_name: F. N. M.
  full_name: Froning, F. N. M.
  last_name: Froning
- first_name: H.
  full_name: Moon, H.
  last_name: Moon
- first_name: M. A.
  full_name: Osborne, M. A.
  last_name: Osborne
- first_name: D.
  full_name: Sejdinovic, D.
  last_name: Sejdinovic
- first_name: Georgios
  full_name: Katsaros, Georgios
  id: 38DB5788-F248-11E8-B48F-1D18A9856A87
  last_name: Katsaros
  orcid: 0000-0001-8342-202X
- first_name: D. M.
  full_name: Zumbühl, D. M.
  last_name: Zumbühl
- first_name: G. A. D.
  full_name: Briggs, G. A. D.
  last_name: Briggs
- first_name: N.
  full_name: Ares, N.
  last_name: Ares
citation:
  ama: Severin B, Lennon DT, Camenzind LC, et al. Cross-architecture tuning of silicon
    and SiGe-based quantum devices using machine learning. <i>arXiv</i>. doi:<a href="https://doi.org/10.48550/arXiv.2107.12975">10.48550/arXiv.2107.12975</a>
  apa: Severin, B., Lennon, D. T., Camenzind, L. C., Vigneau, F., Fedele, F., Jirovec,
    D., … Ares, N. (n.d.). Cross-architecture tuning of silicon and SiGe-based quantum
    devices using machine learning. <i>arXiv</i>. <a href="https://doi.org/10.48550/arXiv.2107.12975">https://doi.org/10.48550/arXiv.2107.12975</a>
  chicago: Severin, B., D. T. Lennon, L. C. Camenzind, F. Vigneau, F. Fedele, Daniel
    Jirovec, A. Ballabio, et al. “Cross-Architecture Tuning of Silicon and SiGe-Based
    Quantum Devices Using Machine Learning.” <i>ArXiv</i>, n.d. <a href="https://doi.org/10.48550/arXiv.2107.12975">https://doi.org/10.48550/arXiv.2107.12975</a>.
  ieee: B. Severin <i>et al.</i>, “Cross-architecture tuning of silicon and SiGe-based
    quantum devices using machine learning,” <i>arXiv</i>. .
  ista: Severin B, Lennon DT, Camenzind LC, Vigneau F, Fedele F, Jirovec D, Ballabio
    A, Chrastina D, Isella G, Kruijf M de, Carballido MJ, Svab S, Kuhlmann AV, Braakman
    FR, Geyer S, Froning FNM, Moon H, Osborne MA, Sejdinovic D, Katsaros G, Zumbühl
    DM, Briggs GAD, Ares N. Cross-architecture tuning of silicon and SiGe-based quantum
    devices using machine learning. arXiv, 2107.12975.
  mla: Severin, B., et al. “Cross-Architecture Tuning of Silicon and SiGe-Based Quantum
    Devices Using Machine Learning.” <i>ArXiv</i>, 2107.12975, doi:<a href="https://doi.org/10.48550/arXiv.2107.12975">10.48550/arXiv.2107.12975</a>.
  short: B. Severin, D.T. Lennon, L.C. Camenzind, F. Vigneau, F. Fedele, D. Jirovec,
    A. Ballabio, D. Chrastina, G. Isella, M. de Kruijf, M.J. Carballido, S. Svab,
    A.V. Kuhlmann, F.R. Braakman, S. Geyer, F.N.M. Froning, H. Moon, M.A. Osborne,
    D. Sejdinovic, G. Katsaros, D.M. Zumbühl, G.A.D. Briggs, N. Ares, ArXiv (n.d.).
date_created: 2021-10-01T12:40:22Z
date_published: 2021-07-27T00:00:00Z
date_updated: 2024-03-25T23:30:14Z
day: '27'
department:
- _id: GeKa
doi: 10.48550/arXiv.2107.12975
external_id:
  arxiv:
  - '2107.12975'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2107.12975
month: '07'
oa: 1
oa_version: Preprint
project:
- _id: 2641CE5E-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: P30207
  name: Hole spin orbit qubits in Ge quantum wells
publication: arXiv
publication_status: submitted
related_material:
  record:
  - id: '10058'
    relation: dissertation_contains
    status: public
status: public
title: Cross-architecture tuning of silicon and SiGe-based quantum devices using machine
  learning
type: preprint
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2021'
...
---
_id: '10559'
abstract:
- lang: eng
  text: Hole gases in planar germanium can have high mobilities in combination with
    strong spin-orbit interaction and electrically tunable g factors, and are therefore
    emerging as a promising platform for creating hybrid superconductor-semiconductor
    devices. A key challenge towards hybrid Ge-based quantum technologies is the design
    of high-quality interfaces and superconducting contacts that are robust against
    magnetic fields. In this work, by combining the assets of aluminum, which provides
    good contact to the Ge, and niobium, which has a significant superconducting gap,
    we demonstrate highly transparent low-disordered JoFETs with relatively large
    ICRN products that are capable of withstanding high magnetic fields. We furthermore
    demonstrate the ability of phase-biasing individual JoFETs, opening up an avenue
    to explore topological superconductivity in planar Ge. The persistence of superconductivity
    in the reported hybrid devices beyond 1.8 T paves the way towards integrating
    spin qubits and proximity-induced superconductivity on the same chip.
acknowledged_ssus:
- _id: NanoFab
- _id: M-Shop
acknowledgement: This research and related results were made possible with the support
  of the NOMIS Foundation. This research was supported by the Scientific Service Units
  of IST Austria through resources provided by the MIBA Machine Shop and the nanofabrication
  facility, the European Union's Horizon 2020 research and innovation program under
  the Marie Sklodowska-Curie Grant agreement No. 844511 Grant Agreement No. 862046.
  ICN2 acknowledge funding from Generalitat de Catalunya 2017 SGR 327. ICN2 is supported
  by the Severo Ochoa program from Spanish MINECO (Grant No. SEV-2017-0706) and is
  funded by the CERCA Programme/Generalitat de Catalunya. Part of the present work
  has been performed in the framework of Universitat Autnoma de Barcelona Materials
  Science PhD program. The HAADF-STEM microscopy was conducted in the Laboratorio
  de Microscopias Avanzadas at Instituto de Nanociencia de Aragon-Universidad de Zaragoza.
  Authors acknowledge the LMA-INA for offering access to their instruments and expertise.
  We acknowledge support from CSIC Research Platform on Quantum Technologies PTI-001.
  This project has received funding from the European Union's Horizon 2020 research
  and innovation programme under Grant Agreement No. 823717 ESTEEM3. M.B. acknowledges
  support from SUR Generalitat de Catalunya and the EU Social Fund; project ref. 2020
  FI 00103. G.S. and M.V. acknowledge support through a projectruimte grant associated
  with the Netherlands Organization of Scientific Research (NWO). J.D. acknowledges
  support through FRIPRO-project 274853, which is funded by the Research Council of
  Norway.
article_number: L022005
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Kushagra
  full_name: Aggarwal, Kushagra
  id: b22ab905-3539-11eb-84c3-fc159dcd79cb
  last_name: Aggarwal
  orcid: 0000-0001-9985-9293
- first_name: Andrea C
  full_name: Hofmann, Andrea C
  id: 340F461A-F248-11E8-B48F-1D18A9856A87
  last_name: Hofmann
- first_name: Daniel
  full_name: Jirovec, Daniel
  id: 4C473F58-F248-11E8-B48F-1D18A9856A87
  last_name: Jirovec
  orcid: 0000-0002-7197-4801
- 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: Amir
  full_name: Sammak, Amir
  last_name: Sammak
- first_name: Marc
  full_name: Botifoll, Marc
  last_name: Botifoll
- first_name: Sara
  full_name: Martí-Sánchez, Sara
  last_name: Martí-Sánchez
- first_name: Menno
  full_name: Veldhorst, Menno
  last_name: Veldhorst
- first_name: Jordi
  full_name: Arbiol, Jordi
  last_name: Arbiol
- first_name: Giordano
  full_name: Scappucci, Giordano
  last_name: Scappucci
- first_name: Jeroen
  full_name: Danon, Jeroen
  last_name: Danon
- first_name: Georgios
  full_name: Katsaros, Georgios
  id: 38DB5788-F248-11E8-B48F-1D18A9856A87
  last_name: Katsaros
  orcid: 0000-0001-8342-202X
citation:
  ama: Aggarwal K, Hofmann AC, Jirovec D, et al. Enhancement of proximity-induced
    superconductivity in a planar Ge hole gas. <i>Physical Review Research</i>. 2021;3(2).
    doi:<a href="https://doi.org/10.1103/physrevresearch.3.l022005">10.1103/physrevresearch.3.l022005</a>
  apa: Aggarwal, K., Hofmann, A. C., Jirovec, D., Prieto Gonzalez, I., Sammak, A.,
    Botifoll, M., … Katsaros, G. (2021). Enhancement of proximity-induced superconductivity
    in a planar Ge hole gas. <i>Physical Review Research</i>. American Physical Society.
    <a href="https://doi.org/10.1103/physrevresearch.3.l022005">https://doi.org/10.1103/physrevresearch.3.l022005</a>
  chicago: Aggarwal, Kushagra, Andrea C Hofmann, Daniel Jirovec, Ivan Prieto Gonzalez,
    Amir Sammak, Marc Botifoll, Sara Martí-Sánchez, et al. “Enhancement of Proximity-Induced
    Superconductivity in a Planar Ge Hole Gas.” <i>Physical Review Research</i>. American
    Physical Society, 2021. <a href="https://doi.org/10.1103/physrevresearch.3.l022005">https://doi.org/10.1103/physrevresearch.3.l022005</a>.
  ieee: K. Aggarwal <i>et al.</i>, “Enhancement of proximity-induced superconductivity
    in a planar Ge hole gas,” <i>Physical Review Research</i>, vol. 3, no. 2. American
    Physical Society, 2021.
  ista: Aggarwal K, Hofmann AC, Jirovec D, Prieto Gonzalez I, Sammak A, Botifoll M,
    Martí-Sánchez S, Veldhorst M, Arbiol J, Scappucci G, Danon J, Katsaros G. 2021.
    Enhancement of proximity-induced superconductivity in a planar Ge hole gas. Physical
    Review Research. 3(2), L022005.
  mla: Aggarwal, Kushagra, et al. “Enhancement of Proximity-Induced Superconductivity
    in a Planar Ge Hole Gas.” <i>Physical Review Research</i>, vol. 3, no. 2, L022005,
    American Physical Society, 2021, doi:<a href="https://doi.org/10.1103/physrevresearch.3.l022005">10.1103/physrevresearch.3.l022005</a>.
  short: K. Aggarwal, A.C. Hofmann, D. Jirovec, I. Prieto Gonzalez, A. Sammak, M.
    Botifoll, S. Martí-Sánchez, M. Veldhorst, J. Arbiol, G. Scappucci, J. Danon, G.
    Katsaros, Physical Review Research 3 (2021).
date_created: 2021-12-16T18:50:57Z
date_published: 2021-04-15T00:00:00Z
date_updated: 2024-02-21T12:41:26Z
day: '15'
ddc:
- '620'
department:
- _id: GeKa
doi: 10.1103/physrevresearch.3.l022005
ec_funded: 1
external_id:
  arxiv:
  - '2012.00322'
file:
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  date_created: 2021-12-17T08:12:37Z
  date_updated: 2021-12-17T08:12:37Z
  file_id: '10561'
  file_name: 2021_PhysRevResearch_Aggarwal.pdf
  file_size: 1917512
  relation: main_file
  success: 1
file_date_updated: 2021-12-17T08:12:37Z
has_accepted_license: '1'
intvolume: '         3'
issue: '2'
keyword:
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language:
- iso: eng
month: '04'
oa: 1
oa_version: Published Version
project:
- _id: 26A151DA-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '844511'
  name: Majorana bound states in Ge/SiGe heterostructures
- _id: 237E5020-32DE-11EA-91FC-C7463DDC885E
  call_identifier: H2020
  grant_number: '862046'
  name: TOPOLOGICALLY PROTECTED AND SCALABLE QUANTUM BITS
publication: Physical Review Research
publication_identifier:
  issn:
  - 2643-1564
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
related_material:
  record:
  - id: '8831'
    relation: earlier_version
    status: public
  - id: '8834'
    relation: research_data
    status: public
scopus_import: '1'
status: public
title: Enhancement of proximity-induced superconductivity in a planar Ge hole gas
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: 8b945eb4-e2f2-11eb-945a-df72226e66a9
volume: 3
year: '2021'
...
---
_id: '8831'
abstract:
- lang: eng
  text: Holes in planar Ge have high mobilities, strong spin-orbit interaction and
    electrically tunable g-factors, and are therefore emerging as a promising candidate
    for hybrid superconductorsemiconductor devices. This is further motivated by the
    observation of supercurrent transport in planar Ge Josephson Field effect transistors
    (JoFETs). A key challenge towards hybrid germanium quantum technology is the design
    of high quality interfaces and superconducting contacts that are robust against
    magnetic fields. By combining the assets of Al, which has a long superconducting
    coherence, and Nb, which has a significant superconducting gap, we form low-disordered
    JoFETs with large ICRN products that are capable of withstanding high magnetic
    fields. We furthermore demonstrate the ability of phase-biasing individual JoFETs
    opening up an avenue to explore topological superconductivity in planar Ge. The
    persistence of superconductivity in the reported hybrid devices beyond 1.8 T paves
    the way towards integrating spin qubits and proximity-induced superconductivity
    on the same chip.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: "This research and related results were made possible with the support
  of the NOMIS Foundation. This research was supported by the Scientific Service Units
  of IST Austria through resources provided by the MIBA Machine Shop and the nanofabrication
  facility, the European Union’s Horizon 2020 research and innovation program under
  the Marie Sklodowska-Curie grant agreement #844511 and the Grant Agreement #862046.
  ICN2 acknowledge funding from Generalitat de Catalunya 2017 SGR 327. ICN2 is supported
  by the Severo Ochoa\r\nprogram from Spanish MINECO (Grant No. SEV2017-0706) and
  is funded by the CERCA Programme / Generalitat de Catalunya. Part of the present
  work has been performed in the framework of Universitat Aut`onoma de Barcelona Materials
  Science PhD program. The HAADF-STEM microscopy was conducted in the Laboratorio
  de Microscopias Avanzadas at Instituto de Nanociencia de Aragon-Universidad de Zaragoza.
  Authors acknowledge the LMA-INA for offering access to their instruments and expertise.
  We acknowledge support from CSIC Research Platform on Quantum Technologies PTI-001.
  This project has received funding from\r\nthe European Union’s Horizon 2020 research
  and innovation programme under grant agreement No 823717 – ESTEEM3. M.B. acknowledges
  support from SUR Generalitat de Catalunya and the EU Social Fund; project ref. 2020
  FI 00103. GS and MV acknowledge support through a projectruimte grant associated
  with the Netherlands Organization of Scientific Research (NWO)."
article_number: '2012.00322'
article_processing_charge: No
arxiv: 1
author:
- first_name: Kushagra
  full_name: Aggarwal, Kushagra
  id: b22ab905-3539-11eb-84c3-fc159dcd79cb
  last_name: Aggarwal
  orcid: 0000-0001-9985-9293
- first_name: Andrea C
  full_name: Hofmann, Andrea C
  id: 340F461A-F248-11E8-B48F-1D18A9856A87
  last_name: Hofmann
- first_name: Daniel
  full_name: Jirovec, Daniel
  id: 4C473F58-F248-11E8-B48F-1D18A9856A87
  last_name: Jirovec
  orcid: 0000-0002-7197-4801
- 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: Amir
  full_name: Sammak, Amir
  last_name: Sammak
- first_name: Marc
  full_name: Botifoll, Marc
  last_name: Botifoll
- first_name: Sara
  full_name: Marti-Sanchez, Sara
  last_name: Marti-Sanchez
- first_name: Menno
  full_name: Veldhorst, Menno
  last_name: Veldhorst
- first_name: Jordi
  full_name: Arbiol, Jordi
  last_name: Arbiol
- first_name: Giordano
  full_name: Scappucci, Giordano
  last_name: Scappucci
- first_name: Georgios
  full_name: Katsaros, Georgios
  id: 38DB5788-F248-11E8-B48F-1D18A9856A87
  last_name: Katsaros
  orcid: 0000-0001-8342-202X
citation:
  ama: Aggarwal K, Hofmann AC, Jirovec D, et al. Enhancement of proximity induced
    superconductivity in planar Germanium. <i>arXiv</i>.
  apa: Aggarwal, K., Hofmann, A. C., Jirovec, D., Prieto Gonzalez, I., Sammak, A.,
    Botifoll, M., … Katsaros, G. (n.d.). Enhancement of proximity induced superconductivity
    in planar Germanium. <i>arXiv</i>.
  chicago: Aggarwal, Kushagra, Andrea C Hofmann, Daniel Jirovec, Ivan Prieto Gonzalez,
    Amir Sammak, Marc Botifoll, Sara Marti-Sanchez, et al. “Enhancement of Proximity
    Induced Superconductivity in Planar Germanium.” <i>ArXiv</i>, n.d.
  ieee: K. Aggarwal <i>et al.</i>, “Enhancement of proximity induced superconductivity
    in planar Germanium,” <i>arXiv</i>. .
  ista: Aggarwal K, Hofmann AC, Jirovec D, Prieto Gonzalez I, Sammak A, Botifoll M,
    Marti-Sanchez S, Veldhorst M, Arbiol J, Scappucci G, Katsaros G. Enhancement of
    proximity induced superconductivity in planar Germanium. arXiv, 2012.00322.
  mla: Aggarwal, Kushagra, et al. “Enhancement of Proximity Induced Superconductivity
    in Planar Germanium.” <i>ArXiv</i>, 2012.00322.
  short: K. Aggarwal, A.C. Hofmann, D. Jirovec, I. Prieto Gonzalez, A. Sammak, M.
    Botifoll, S. Marti-Sanchez, M. Veldhorst, J. Arbiol, G. Scappucci, G. Katsaros,
    ArXiv (n.d.).
date_created: 2020-12-02T10:42:53Z
date_published: 2020-12-02T00:00:00Z
date_updated: 2024-03-25T23:30:14Z
day: '02'
ddc:
- '530'
department:
- _id: GeKa
ec_funded: 1
external_id:
  arxiv:
  - '2012.00322'
file:
- access_level: open_access
  checksum: 22a612e206232fa94b138b2c2f957582
  content_type: application/pdf
  creator: gkatsaro
  date_created: 2020-12-02T10:42:31Z
  date_updated: 2020-12-02T10:42:31Z
  file_id: '8832'
  file_name: Superconducting_2D_Ge.pdf
  file_size: 1697939
  relation: main_file
file_date_updated: 2020-12-02T10:42:31Z
has_accepted_license: '1'
language:
- iso: eng
month: '12'
oa: 1
oa_version: Submitted Version
project:
- _id: 262116AA-B435-11E9-9278-68D0E5697425
  name: Hybrid Semiconductor - Superconductor Quantum Devices
- _id: 26A151DA-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '844511'
  name: Majorana bound states in Ge/SiGe heterostructures
- _id: 237E5020-32DE-11EA-91FC-C7463DDC885E
  call_identifier: H2020
  grant_number: '862046'
  name: TOPOLOGICALLY PROTECTED AND SCALABLE QUANTUM BITS
publication: arXiv
publication_status: submitted
related_material:
  record:
  - id: '10559'
    relation: later_version
    status: public
  - id: '8834'
    relation: research_data
    status: public
  - id: '10058'
    relation: dissertation_contains
    status: public
status: public
title: Enhancement of proximity induced superconductivity in planar Germanium
type: preprint
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2020'
...
---
_id: '10065'
abstract:
- lang: eng
  text: We study double quantum dots in a Ge/SiGe heterostructure and test their maturity
    towards singlet-triplet ($S-T_0$) qubits. We demonstrate a large range of tunability,
    from two single quantum dots to a double quantum dot. We measure Pauli spin blockade
    and study the anisotropy of the $g$-factor. We use an adjacent quantum dot for
    sensing charge transitions in the double quantum dot at interest. In conclusion,
    Ge/SiGe possesses all ingredients necessary for building a singlet-triplet qubit.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: "We thank Matthias Brauns for helpful discussions and careful proofreading
  of the manuscript. This project has received funding from the European Union’s Horizon
  2020 research and innovation program under the Marie Sklodowska-Curie grant agreement
  No 844511 and from the FWF project P30207. The research was supported by the Scientific
  Service Units of IST Austria through resources provided by the MIBA machine shop
  and the nanofabrication\r\nfacility."
article_number: '1910.05841'
article_processing_charge: No
arxiv: 1
author:
- first_name: Andrea C
  full_name: Hofmann, Andrea C
  id: 340F461A-F248-11E8-B48F-1D18A9856A87
  last_name: Hofmann
- first_name: Daniel
  full_name: Jirovec, Daniel
  id: 4C473F58-F248-11E8-B48F-1D18A9856A87
  last_name: Jirovec
  orcid: 0000-0002-7197-4801
- first_name: Maxim
  full_name: Borovkov, Maxim
  last_name: Borovkov
- 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: Andrea
  full_name: Ballabio, Andrea
  last_name: Ballabio
- first_name: Jacopo
  full_name: Frigerio, Jacopo
  last_name: Frigerio
- 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: Hofmann AC, Jirovec D, Borovkov M, et al. Assessing the potential of Ge/SiGe
    quantum dots as hosts for singlet-triplet qubits. <i>arXiv</i>. doi:<a href="https://doi.org/10.48550/arXiv.1910.05841">10.48550/arXiv.1910.05841</a>
  apa: Hofmann, A. C., Jirovec, D., Borovkov, M., Prieto Gonzalez, I., Ballabio, A.,
    Frigerio, J., … Katsaros, G. (n.d.). Assessing the potential of Ge/SiGe quantum
    dots as hosts for singlet-triplet qubits. <i>arXiv</i>. <a href="https://doi.org/10.48550/arXiv.1910.05841">https://doi.org/10.48550/arXiv.1910.05841</a>
  chicago: Hofmann, Andrea C, Daniel Jirovec, Maxim Borovkov, Ivan Prieto Gonzalez,
    Andrea Ballabio, Jacopo Frigerio, Daniel Chrastina, Giovanni Isella, and Georgios
    Katsaros. “Assessing the Potential of Ge/SiGe Quantum Dots as Hosts for Singlet-Triplet
    Qubits.” <i>ArXiv</i>, n.d. <a href="https://doi.org/10.48550/arXiv.1910.05841">https://doi.org/10.48550/arXiv.1910.05841</a>.
  ieee: A. C. Hofmann <i>et al.</i>, “Assessing the potential of Ge/SiGe quantum dots
    as hosts for singlet-triplet qubits,” <i>arXiv</i>. .
  ista: Hofmann AC, Jirovec D, Borovkov M, Prieto Gonzalez I, Ballabio A, Frigerio
    J, Chrastina D, Isella G, Katsaros G. Assessing the potential of Ge/SiGe quantum
    dots as hosts for singlet-triplet qubits. arXiv, 1910.05841.
  mla: Hofmann, Andrea C., et al. “Assessing the Potential of Ge/SiGe Quantum Dots
    as Hosts for Singlet-Triplet Qubits.” <i>ArXiv</i>, 1910.05841, doi:<a href="https://doi.org/10.48550/arXiv.1910.05841">10.48550/arXiv.1910.05841</a>.
  short: A.C. Hofmann, D. Jirovec, M. Borovkov, I. Prieto Gonzalez, A. Ballabio, J.
    Frigerio, D. Chrastina, G. Isella, G. Katsaros, ArXiv (n.d.).
date_created: 2021-10-01T12:14:51Z
date_published: 2019-10-13T00:00:00Z
date_updated: 2024-03-25T23:30:14Z
day: '13'
department:
- _id: GeKa
doi: 10.48550/arXiv.1910.05841
ec_funded: 1
external_id:
  arxiv:
  - '1910.05841'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1910.05841
month: '10'
oa: 1
oa_version: Preprint
project:
- _id: 26A151DA-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '844511'
  name: Majorana bound states in Ge/SiGe heterostructures
- _id: 2641CE5E-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: P30207
  name: Hole spin orbit qubits in Ge quantum wells
publication: arXiv
publication_status: submitted
related_material:
  record:
  - id: '10058'
    relation: dissertation_contains
    status: public
status: public
title: Assessing the potential of Ge/SiGe quantum dots as hosts for singlet-triplet
  qubits
type: preprint
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2019'
...
---
_id: '5816'
abstract:
- lang: eng
  text: Solid-state qubit manipulation and read-out fidelities are reaching fault-tolerance,
    but quantum error correction requires millions of physical qubits and therefore
    a scalable quantum computer architecture. To solve signal-line bandwidth and fan-out
    problems, microwave sources required for qubit manipulation might be embedded
    close to the qubit chip, typically operating at temperatures below 4 K. Here,
    we perform the first low temperature measurements of a 130 nm BiCMOS based SiGe
    voltage controlled oscillator at cryogenic temperature. We determined the frequency
    and output power dependence on temperature and magnetic field up to 5 T and measured
    the temperature influence on its noise performance. The device maintains its full
    functionality from 300 K to 4 K. The carrier frequency at 4 K increases by 3%
    with respect to the carrier frequency at 300 K, and the output power at 4 K increases
    by 10 dB relative to the output power at 300 K. The frequency tuning range of
    approximately 20% remains unchanged between 300 K and 4 K. In an in-plane magnetic
    field of 5 T, the carrier frequency shifts by only 0.02% compared to the frequency
    at zero magnetic field.
article_number: '114701'
article_processing_charge: No
arxiv: 1
author:
- first_name: Arne
  full_name: Hollmann, Arne
  last_name: Hollmann
- first_name: Daniel
  full_name: Jirovec, Daniel
  id: 4C473F58-F248-11E8-B48F-1D18A9856A87
  last_name: Jirovec
  orcid: 0000-0002-7197-4801
- first_name: Maciej
  full_name: Kucharski, Maciej
  last_name: Kucharski
- first_name: Dietmar
  full_name: Kissinger, Dietmar
  last_name: Kissinger
- first_name: Gunter
  full_name: Fischer, Gunter
  last_name: Fischer
- first_name: Lars R.
  full_name: Schreiber, Lars R.
  last_name: Schreiber
citation:
  ama: Hollmann A, Jirovec D, Kucharski M, Kissinger D, Fischer G, Schreiber LR. 30
    GHz-voltage controlled oscillator operating at 4 K. <i>Review of Scientific Instruments</i>.
    2018;89(11). doi:<a href="https://doi.org/10.1063/1.5038258">10.1063/1.5038258</a>
  apa: Hollmann, A., Jirovec, D., Kucharski, M., Kissinger, D., Fischer, G., &#38;
    Schreiber, L. R. (2018). 30 GHz-voltage controlled oscillator operating at 4 K.
    <i>Review of Scientific Instruments</i>. AIP Publishing. <a href="https://doi.org/10.1063/1.5038258">https://doi.org/10.1063/1.5038258</a>
  chicago: Hollmann, Arne, Daniel Jirovec, Maciej Kucharski, Dietmar Kissinger, Gunter
    Fischer, and Lars R. Schreiber. “30 GHz-Voltage Controlled Oscillator Operating
    at 4 K.” <i>Review of Scientific Instruments</i>. AIP Publishing, 2018. <a href="https://doi.org/10.1063/1.5038258">https://doi.org/10.1063/1.5038258</a>.
  ieee: A. Hollmann, D. Jirovec, M. Kucharski, D. Kissinger, G. Fischer, and L. R.
    Schreiber, “30 GHz-voltage controlled oscillator operating at 4 K,” <i>Review
    of Scientific Instruments</i>, vol. 89, no. 11. AIP Publishing, 2018.
  ista: Hollmann A, Jirovec D, Kucharski M, Kissinger D, Fischer G, Schreiber LR.
    2018. 30 GHz-voltage controlled oscillator operating at 4 K. Review of Scientific
    Instruments. 89(11), 114701.
  mla: Hollmann, Arne, et al. “30 GHz-Voltage Controlled Oscillator Operating at 4
    K.” <i>Review of Scientific Instruments</i>, vol. 89, no. 11, 114701, AIP Publishing,
    2018, doi:<a href="https://doi.org/10.1063/1.5038258">10.1063/1.5038258</a>.
  short: A. Hollmann, D. Jirovec, M. Kucharski, D. Kissinger, G. Fischer, L.R. Schreiber,
    Review of Scientific Instruments 89 (2018).
date_created: 2019-01-10T14:22:23Z
date_published: 2018-11-01T00:00:00Z
date_updated: 2024-03-25T23:30:14Z
day: '01'
department:
- _id: GeKa
doi: 10.1063/1.5038258
external_id:
  arxiv:
  - '1804.09522'
  isi:
  - '000451735700054'
intvolume: '        89'
isi: 1
issue: '11'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1804.09522
month: '11'
oa: 1
oa_version: Preprint
publication: Review of Scientific Instruments
publication_identifier:
  issn:
  - '00346748'
publication_status: published
publisher: AIP Publishing
quality_controlled: '1'
related_material:
  record:
  - id: '10058'
    relation: dissertation_contains
    status: public
scopus_import: '1'
status: public
title: 30 GHz-voltage controlled oscillator operating at 4 K
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 89
year: '2018'
...