---
_id: '13286'
abstract:
- lang: eng
  text: Semiconductor-superconductor hybrid systems are the harbour of many intriguing
    mesoscopic phenomena. This material combination leads to spatial variations of
    the superconducting properties, which gives rise to Andreev bound states (ABSs).
    Some of these states might exhibit remarkable properties that render them highly
    desirable for topological quantum computing. The most prominent and hunted of
    such states are Majorana zero modes (MZMs), quasiparticles equals to their own
    quasiparticles that they follow non-abelian statistics. In this thesis, we first
    introduce the general framework of such hybrid systems and, then, we unveil a
    series of mesoscopic phenomena that we discovered. Firstly, we show tunneling
    spectroscopy experiments on full-shell nanowires (NWs) showing that unwanted quantum-dot
    states coupled to superconductors (Yu-Shiba-Rusinov states) can mimic MZMs signatures.
    Then, we introduce a novel protocol which allowed the integration of tunneling
    spectroscopy with Coulomb spectroscopy within the same device. Employing this
    approach on both full-shell NWs and partial-shell NWs, we demonstrated that longitudinally
    confined states reveal charge transport phenomenology similar to the one expected
    for MZMs. These findings shed light on the intricate interplay between superconductivity
    and quantum confinement, which brought us to explore another material platform,
    i.e. a two-dimensional Germanium hole gas. After developing a robust way to induce
    superconductivity in such system, we showed how to engineer the proximity effect
    and we revealed a superconducting hard gap. Finally, we created a superconducting
    radio frequency driven ideal diode and a generator of non-sinusoidal current-phase
    relations. Our results open the path for the exploration of protected superconducting
    qubits and more complex hybrid devices in planar Germanium, like Kitaev chains
    and hybrid qubit devices.
acknowledged_ssus:
- _id: NanoFab
- _id: M-Shop
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Marco
  full_name: Valentini, Marco
  id: C0BB2FAC-D767-11E9-B658-BC13E6697425
  last_name: Valentini
citation:
  ama: 'Valentini M. Mesoscopic phenomena in hybrid semiconductor-superconductor nanodevices :
    From full-shell nanowires to two-dimensional hole gas in germanium. 2023. doi:<a
    href="https://doi.org/10.15479/at:ista:13286">10.15479/at:ista:13286</a>'
  apa: 'Valentini, M. (2023). <i>Mesoscopic phenomena in hybrid semiconductor-superconductor
    nanodevices : From full-shell nanowires to two-dimensional hole gas in germanium</i>.
    Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/at:ista:13286">https://doi.org/10.15479/at:ista:13286</a>'
  chicago: 'Valentini, Marco. “Mesoscopic Phenomena in Hybrid Semiconductor-Superconductor
    Nanodevices : From Full-Shell Nanowires to Two-Dimensional Hole Gas in Germanium.”
    Institute of Science and Technology Austria, 2023. <a href="https://doi.org/10.15479/at:ista:13286">https://doi.org/10.15479/at:ista:13286</a>.'
  ieee: 'M. Valentini, “Mesoscopic phenomena in hybrid semiconductor-superconductor
    nanodevices : From full-shell nanowires to two-dimensional hole gas in germanium,”
    Institute of Science and Technology Austria, 2023.'
  ista: 'Valentini M. 2023. Mesoscopic phenomena in hybrid semiconductor-superconductor
    nanodevices : From full-shell nanowires to two-dimensional hole gas in germanium.
    Institute of Science and Technology Austria.'
  mla: 'Valentini, Marco. <i>Mesoscopic Phenomena in Hybrid Semiconductor-Superconductor
    Nanodevices : From Full-Shell Nanowires to Two-Dimensional Hole Gas in Germanium</i>.
    Institute of Science and Technology Austria, 2023, doi:<a href="https://doi.org/10.15479/at:ista:13286">10.15479/at:ista:13286</a>.'
  short: 'M. Valentini, Mesoscopic Phenomena in Hybrid Semiconductor-Superconductor
    Nanodevices : From Full-Shell Nanowires to Two-Dimensional Hole Gas in Germanium,
    Institute of Science and Technology Austria, 2023.'
date_created: 2023-07-24T14:10:45Z
date_published: 2023-07-21T00:00:00Z
date_updated: 2024-02-21T12:35:34Z
day: '21'
ddc:
- '530'
degree_awarded: PhD
department:
- _id: GradSch
- _id: GeKa
doi: 10.15479/at:ista:13286
ec_funded: 1
file:
- access_level: closed
  checksum: 666ee31c7eade89679806287c062fa14
  content_type: application/x-zip-compressed
  creator: mvalenti
  date_created: 2023-08-11T09:27:39Z
  date_updated: 2023-08-11T10:01:34Z
  file_id: '14033'
  file_name: PhD_thesis_Valentini_final.zip
  file_size: 56121429
  relation: source_file
- access_level: open_access
  checksum: 0992f2ebef152dee8e70055350ebbb55
  content_type: application/pdf
  creator: mvalenti
  date_created: 2023-08-11T14:39:17Z
  date_updated: 2023-08-11T14:39:17Z
  file_id: '14035'
  file_name: PhD_thesis_Valentini_final_validated.pdf
  file_size: 38199711
  relation: main_file
file_date_updated: 2023-08-11T14:39:17Z
has_accepted_license: '1'
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc-sa/4.0/
month: '07'
oa: 1
oa_version: Published Version
page: '184'
project:
- _id: 262116AA-B435-11E9-9278-68D0E5697425
  name: Hybrid Semiconductor - Superconductor Quantum Devices
- _id: 237E5020-32DE-11EA-91FC-C7463DDC885E
  call_identifier: H2020
  grant_number: '862046'
  name: TOPOLOGICALLY PROTECTED AND SCALABLE QUANTUM BITS
- _id: 34a66131-11ca-11ed-8bc3-a31681c6b03e
  grant_number: F8606
  name: Conventional and unconventional topological superconductors
publication_identifier:
  issn:
  - 2663 - 337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '13312'
    relation: part_of_dissertation
    status: public
  - id: '12118'
    relation: part_of_dissertation
    status: public
  - id: '8910'
    relation: part_of_dissertation
    status: public
  - id: '12522'
    relation: research_data
    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: 'Mesoscopic phenomena in hybrid semiconductor-superconductor nanodevices :
  From full-shell nanowires to two-dimensional hole gas in germanium'
tmp:
  image: /images/cc_by_nc_sa.png
  legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode
  name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC
    BY-NC-SA 4.0)
  short: CC BY-NC-SA (4.0)
type: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2023'
...
---
_id: '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: '8910'
abstract:
- lang: eng
  text: A semiconducting nanowire fully wrapped by a superconducting shell has been
    proposed as a platform for obtaining Majorana modes at small magnetic fields.
    In this study, we demonstrate that the appearance of subgap states in such structures
    is actually governed by the junction region in tunneling spectroscopy measurements
    and not the full-shell nanowire itself. Short tunneling regions never show subgap
    states, whereas longer junctions always do. This can be understood in terms of
    quantum dots forming in the junction and hosting Andreev levels in the Yu-Shiba-Rusinov
    regime. The intricate magnetic field dependence of the Andreev levels, through
    both the Zeeman and Little-Parks effects, may result in robust zero-bias peaks—features
    that could be easily misinterpreted as originating from Majorana zero modes but
    are unrelated to topological superconductivity.
acknowledged_ssus:
- _id: M-Shop
- _id: NanoFab
acknowledgement: The authors thank A. Higginbotham, E. J. H. Lee and F. R. Martins
  for helpful discussions. 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 NOMIS Foundation and Microsoft; the European Union’s Horizon 2020
  research and innovation program under the Marie SklodowskaCurie grant agreement
  No 844511; the FETOPEN Grant Agreement No. 828948; the European Research Commission
  through the grant agreement HEMs-DAM No 716655; the Spanish Ministry of Science
  and Innovation through Grants PGC2018-097018-B-I00, PCI2018-093026, FIS2016-80434-P
  (AEI/FEDER, EU), RYC2011-09345 (Ram´on y Cajal Programme), and the Mar´ıa de Maeztu
  Programme for Units of Excellence in R&D (CEX2018-000805-M); the CSIC Research Platform
  on Quantum Technologies PTI-001.
article_number: 82-88
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Marco
  full_name: Valentini, Marco
  id: C0BB2FAC-D767-11E9-B658-BC13E6697425
  last_name: Valentini
- first_name: Fernando
  full_name: Peñaranda, Fernando
  last_name: Peñaranda
- first_name: Andrea C
  full_name: Hofmann, Andrea C
  id: 340F461A-F248-11E8-B48F-1D18A9856A87
  last_name: Hofmann
- first_name: Matthias
  full_name: Brauns, Matthias
  id: 33F94E3C-F248-11E8-B48F-1D18A9856A87
  last_name: Brauns
- first_name: Robert
  full_name: Hauschild, Robert
  id: 4E01D6B4-F248-11E8-B48F-1D18A9856A87
  last_name: Hauschild
  orcid: 0000-0001-9843-3522
- first_name: Peter
  full_name: Krogstrup, Peter
  last_name: Krogstrup
- first_name: Pablo
  full_name: San-Jose, Pablo
  last_name: San-Jose
- first_name: Elsa
  full_name: Prada, Elsa
  last_name: Prada
- first_name: Ramón
  full_name: Aguado, Ramón
  last_name: Aguado
- first_name: Georgios
  full_name: Katsaros, Georgios
  id: 38DB5788-F248-11E8-B48F-1D18A9856A87
  last_name: Katsaros
  orcid: 0000-0001-8342-202X
citation:
  ama: Valentini M, Peñaranda F, Hofmann AC, et al. Nontopological zero-bias peaks
    in full-shell nanowires induced by flux-tunable Andreev states. <i>Science</i>.
    2021;373(6550). doi:<a href="https://doi.org/10.1126/science.abf1513">10.1126/science.abf1513</a>
  apa: Valentini, M., Peñaranda, F., Hofmann, A. C., Brauns, M., Hauschild, R., Krogstrup,
    P., … Katsaros, G. (2021). Nontopological zero-bias peaks in full-shell nanowires
    induced by flux-tunable Andreev states. <i>Science</i>. American Association for
    the Advancement of Science. <a href="https://doi.org/10.1126/science.abf1513">https://doi.org/10.1126/science.abf1513</a>
  chicago: Valentini, Marco, Fernando Peñaranda, Andrea C Hofmann, Matthias Brauns,
    Robert Hauschild, Peter Krogstrup, Pablo San-Jose, Elsa Prada, Ramón Aguado, and
    Georgios Katsaros. “Nontopological Zero-Bias Peaks in Full-Shell Nanowires Induced
    by Flux-Tunable Andreev States.” <i>Science</i>. American Association for the
    Advancement of Science, 2021. <a href="https://doi.org/10.1126/science.abf1513">https://doi.org/10.1126/science.abf1513</a>.
  ieee: M. Valentini <i>et al.</i>, “Nontopological zero-bias peaks in full-shell
    nanowires induced by flux-tunable Andreev states,” <i>Science</i>, vol. 373, no.
    6550. American Association for the Advancement of Science, 2021.
  ista: Valentini M, Peñaranda F, Hofmann AC, Brauns M, Hauschild R, Krogstrup P,
    San-Jose P, Prada E, Aguado R, Katsaros G. 2021. Nontopological zero-bias peaks
    in full-shell nanowires induced by flux-tunable Andreev states. Science. 373(6550),
    82–88.
  mla: Valentini, Marco, et al. “Nontopological Zero-Bias Peaks in Full-Shell Nanowires
    Induced by Flux-Tunable Andreev States.” <i>Science</i>, vol. 373, no. 6550, 82–88,
    American Association for the Advancement of Science, 2021, doi:<a href="https://doi.org/10.1126/science.abf1513">10.1126/science.abf1513</a>.
  short: M. Valentini, F. Peñaranda, A.C. Hofmann, M. Brauns, R. Hauschild, P. Krogstrup,
    P. San-Jose, E. Prada, R. Aguado, G. Katsaros, Science 373 (2021).
date_created: 2020-12-02T10:51:52Z
date_published: 2021-07-02T00:00:00Z
date_updated: 2024-02-21T12:40:09Z
day: '02'
department:
- _id: GeKa
- _id: Bio
doi: 10.1126/science.abf1513
ec_funded: 1
external_id:
  arxiv:
  - '2008.02348'
  isi:
  - '000677843100034'
intvolume: '       373'
isi: 1
issue: '6550'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/2008.02348
month: '07'
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
publication: Science
publication_identifier:
  eissn:
  - '10959203'
  issn:
  - '00368075'
publication_status: published
publisher: American Association for the Advancement of Science
quality_controlled: '1'
related_material:
  link:
  - description: News on IST Homepage
    relation: press_release
    url: https://ist.ac.at/en/news/unfinding-a-split-electron/
  record:
  - id: '13286'
    relation: dissertation_contains
    status: public
  - id: '9389'
    relation: research_data
    status: public
scopus_import: '1'
status: public
title: Nontopological zero-bias peaks in full-shell nanowires induced by flux-tunable
  Andreev states
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 373
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'
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language:
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project:
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  name: Hybrid Semiconductor - Superconductor Quantum Devices
- _id: 26A151DA-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
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publication: arXiv
publication_status: submitted
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title: Enhancement of proximity induced superconductivity in planar Germanium
type: preprint
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
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...