1
|
Yang L, Steinhauer S, Strambini E, Lettner T, Schweickert L, Versteegh MAM, Zannier V, Sorba L, Solenov D, Giazotto F. Proximitized Josephson junctions in highly-doped InAs nanowires robust to optical illumination. NANOTECHNOLOGY 2021; 32:075001. [PMID: 33096537 DOI: 10.1088/1361-6528/abc44e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We have studied the effects of optical-frequency light on proximitized InAs/Al Josephson junctions based on highly n-doped InAs nanowires at varying incident photon flux and at three different photon wavelengths. The experimentally obtained IV curves were modeled using a resistively shunted junction model which takes scattering at the contact interfaces into account. Despite the fact that the InAs weak link is photosensitive, the Josephson junctions were found to be surprisingly robust, interacting with the incident radiation only through heating, whereas above the critical current our devices showed non-thermal effects resulting from photon exposure. Our work indicates that Josephson junctions based on highly-doped InAs nanowires can be integrated in close proximity to photonic circuits. The results also suggest that such junctions can be used for optical-frequency photon detection through thermal processes by measuring a shift in critical current.
Collapse
Affiliation(s)
- Lily Yang
- Department of Applied Physics, KTH Royal Institute of Technology, Albanova University Centre, SE-106 91 Stockholm, Sweden
| | - Stephan Steinhauer
- Department of Applied Physics, KTH Royal Institute of Technology, Albanova University Centre, SE-106 91 Stockholm, Sweden
| | - Elia Strambini
- NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, Pisa I-56127, Italy
| | - Thomas Lettner
- Department of Applied Physics, KTH Royal Institute of Technology, Albanova University Centre, SE-106 91 Stockholm, Sweden
| | - Lucas Schweickert
- Department of Applied Physics, KTH Royal Institute of Technology, Albanova University Centre, SE-106 91 Stockholm, Sweden
| | - Marijn A M Versteegh
- Department of Applied Physics, KTH Royal Institute of Technology, Albanova University Centre, SE-106 91 Stockholm, Sweden
| | - Valentina Zannier
- NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, Pisa I-56127, Italy
| | - Lucia Sorba
- NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, Pisa I-56127, Italy
| | - Dmitry Solenov
- Department of Physics, Saint Louis University, St. Louis, MO 63103, United States of America
| | - Francesco Giazotto
- NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, Pisa I-56127, Italy
| |
Collapse
|
2
|
Flux periodic oscillations and phase-coherent transport in GeTe nanowire-based devices. Nat Commun 2021; 12:754. [PMID: 33531502 PMCID: PMC7854721 DOI: 10.1038/s41467-021-21042-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 01/05/2021] [Indexed: 11/09/2022] Open
Abstract
Despite the fact that GeTe is known to be a very interesting material for applications in thermoelectrics and for phase-change memories, the knowledge on its low-temperature transport properties is only limited. We report on phase-coherent phenomena in the magnetotransport of GeTe nanowires. From universal conductance fluctuations measured on GeTe nanowires with Au contacts, a phase-coherence length of about 280 nm at 0.5 K is determined. The distinct phase-coherence is confirmed by the observation of Aharonov-Bohm type oscillations for parallel magnetic fields. We interpret the occurrence of these magnetic flux-periodic oscillations by the formation of a tubular hole accumulation layer. For Nb/GeTe-nanowire/Nb Josephson junctions we obtained a critical current of 0.2 μA at 0.4 K. By applying a perpendicular magnetic field the critical current decreases monotonously with increasing field, whereas in a parallel field the critical current oscillates with a period of the magnetic flux quantum confirming the presence of a tubular hole channel.
Collapse
|
3
|
Wang Q, Liu CC, Lu YM, Zhang F. High-Temperature Majorana Corner States. PHYSICAL REVIEW LETTERS 2018; 121:186801. [PMID: 30444417 DOI: 10.1103/physrevlett.121.186801] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 09/26/2018] [Indexed: 06/09/2023]
Abstract
Majorana bound states often occur at the end of a 1D topological superconductor. Validated by a new bulk invariant and an intuitive edge argument, we show the emergence of one Majorana Kramers pair at each corner of a square-shaped 2D topological insulator proximitized by an s_{±}-wave (e.g., Fe-based) superconductor. We obtain a phase diagram that addresses the relaxation of crystal symmetry and edge orientation. We propose two experimental realizations in candidate materials. Our scheme offers a higher-order and higher-temperature route for exploring non-Abelian quasiparticles.
Collapse
Affiliation(s)
- Qiyue Wang
- Department of Physics, University of Texas at Dallas, Richardson, Texas 75080, USA
| | - Cheng-Cheng Liu
- School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Yuan-Ming Lu
- Department of Physics, Ohio State University, Columbus, Ohio 43210, USA
| | - Fan Zhang
- Department of Physics, University of Texas at Dallas, Richardson, Texas 75080, USA
| |
Collapse
|
4
|
Ridderbos J, Brauns M, Shen J, de Vries FK, Li A, Bakkers EPAM, Brinkman A, Zwanenburg FA. Josephson Effect in a Few-Hole Quantum Dot. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1802257. [PMID: 30260519 DOI: 10.1002/adma.201802257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 07/11/2018] [Indexed: 06/08/2023]
Abstract
A Ge-Si core-shell nanowire is used to realize a Josephson field-effect transistor with highly transparent contacts to superconducting leads. By changing the electric field, access to two distinct regimes, not combined before in a single device, is gained: in the accumulation mode the device is highly transparent and the supercurrent is carried by multiple subbands, while near depletion, the supercurrent is carried by single-particle levels of a strongly coupled quantum dot operating in the few-hole regime. These results establish Ge-Si nanowires as an important platform for hybrid superconductor-semiconductor physics and Majorana fermions.
Collapse
Affiliation(s)
- Joost Ridderbos
- MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands
| | - Matthias Brauns
- MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands
| | - Jie Shen
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA, Delft, The Netherlands
| | - Folkert K de Vries
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA, Delft, The Netherlands
| | - Ang Li
- Department of Applied Physics, Eindhoven University of Technology, Postbox 513, 5600 MB, Eindhoven, The Netherlands
| | - Erik P A M Bakkers
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA, Delft, The Netherlands
- Department of Applied Physics, Eindhoven University of Technology, Postbox 513, 5600 MB, Eindhoven, The Netherlands
| | - Alexander Brinkman
- MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands
| | - Floris A Zwanenburg
- MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands
| |
Collapse
|
5
|
Lee GH, Lee HJ. Proximity coupling in superconductor-graphene heterostructures. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:056502. [PMID: 29451135 DOI: 10.1088/1361-6633/aaafe1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
This review discusses the electronic properties and the prospective research directions of superconductor-graphene heterostructures. The basic electronic properties of graphene are introduced to highlight the unique possibility of combining two seemingly unrelated physics, superconductivity and relativity. We then focus on graphene-based Josephson junctions, one of the most versatile superconducting quantum devices. The various theoretical methods that have been developed to describe graphene Josephson junctions are examined, together with their advantages and limitations, followed by a discussion on the advances in device fabrication and the relevant length scales. The phase-sensitive properties and phase-particle dynamics of graphene Josephson junctions are examined to provide an understanding of the underlying mechanisms of Josephson coupling via graphene. Thereafter, microscopic transport of correlated quasiparticles produced by Andreev reflections at superconducting interfaces and their phase-coherent behaviors are discussed. Quantum phase transitions studied with graphene as an electrostatically tunable 2D platform are reviewed. The interplay between proximity-induced superconductivity and the quantum-Hall phase is discussed as a possible route to study topological superconductivity and non-Abelian physics. Finally, a brief summary on the prospective future research directions is given.
Collapse
Affiliation(s)
- Gil-Ho Lee
- Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea. Department of Physics, Harvard University, Cambridge, MA 02138, United States of America
| | | |
Collapse
|
6
|
Kim J, Kim BK, Kim HS, Hwang A, Kim B, Doh YJ. Macroscopic Quantum Tunneling in Superconducting Junctions of β-Ag 2Se Topological Insulator Nanowire. NANO LETTERS 2017; 17:6997-7002. [PMID: 29064253 DOI: 10.1021/acs.nanolett.7b03571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We report on the fabrication and electrical transport properties of superconducting junctions made of β-Ag2Se topological insulator (TI) nanowires in contact with Al superconducting electrodes. The temperature dependence of the critical current indicates that the superconducting junction belongs to a short and diffusive junction regime. As a characteristic feature of the narrow junction, the critical current decreases monotonously with increasing magnetic field. The stochastic distribution of the switching current exhibits the macroscopic quantum tunneling behavior, which is robust up to T = 0.8 K. Our observations indicate that the TI nanowire-based Josephson junctions can be a promising building block for the development of nanohybrid superconducting quantum bits.
Collapse
Affiliation(s)
- Jihwan Kim
- Department of Chemistry, KAIST , Daejeon 34141, Korea
| | - Bum-Kyu Kim
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology (GIST) , Gwangju 61005, Korea
| | - Hong-Seok Kim
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology (GIST) , Gwangju 61005, Korea
| | - Ahreum Hwang
- Department of Chemistry, KAIST , Daejeon 34141, Korea
| | - Bongsoo Kim
- Department of Chemistry, KAIST , Daejeon 34141, Korea
| | - Yong-Joo Doh
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology (GIST) , Gwangju 61005, Korea
| |
Collapse
|