1
|
Bakhshipour Z, Hosseini MV. Electron-electron interactions in partially mixed helical states. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:395601. [PMID: 38906127 DOI: 10.1088/1361-648x/ad5ad2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Accepted: 06/21/2024] [Indexed: 06/23/2024]
Abstract
We theoretically study the effect of electron-electron interactions in one-dimensional partially mixed helical states. These helical states can be realized at the edges of two-dimensional topological insulators with partially broken time-reversal symmetry, resulting in helical gapped states. Using the bosonization method and renormalization group analysis, we identify weak gap, crossover, and strong gap regimes in the phase diagram. We find that strong electron-electron interaction mixes the helicity of the states, leading to the relevant strong gap regime. We investigate the charge and spin density wave correlation functions in different relevancy regimes of the gap mediated by interactions, where in the case of strong repulsive interaction, the spin density wave dominates the charge density wave. Additionally, employing the Memory function technique, we calculate the effect of mixed helicity on the charge transport in a sufficiently long edge. We find a non-uniform temperature dependence for the charge conductivity in both the strong and weak gap regimes with distinct features.
Collapse
Affiliation(s)
- Zeinab Bakhshipour
- Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791, Iran
| | - Mir Vahid Hosseini
- Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791, Iran
| |
Collapse
|
2
|
Xiong Z, Wen Y, Wang H, Zhang X, Yin L, Cheng R, Tu Y, He J. Van der Waals Epitaxial Growth of Ultrathin Indium Antimonide on Arbitrary Substrates through Low-Thermal Budget. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2402435. [PMID: 38723286 DOI: 10.1002/adma.202402435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 04/17/2024] [Indexed: 05/18/2024]
Abstract
III-V semiconductors possess high mobility, high frequency response, and detection sensitivity, making them potentially attractive for beyond-silicon electronics applications. However, the traditional heteroepitaxy of III-V semiconductors is impeded by a significant lattice mismatch and the necessity for extreme vacuum and high temperature conditions, thereby impeding their in situ compatibility with flexible substrates and silicon-based circuits. In this study, a novel approach is presented for fabricating ultrathin InSb single-crystal nanosheets on arbitrary substrates with a thickness as thin as 2.4 nm using low-thermal-budget van der Waals (vdW) epitaxy through chemical vapor deposition (CVD). In particular, in situ growth has been successfully achieved on both silicon-based substrates and flexible polyimide (PI) substrates. Notably, the growth temperature required for InSb nanosheets (240 °C) is significantly lower than that employed in back-end-of-line processes (400 °C). The field effect transistor devices based on fabricated ultrathin InSb nanosheets exhibit ultra-high on-off ratio exceeding 108 and demonstrate minimal gate leakage currents. Furthermore, these ultrathin InSb nanosheets display p-type characteristics with hole mobilities reaching up to 203 cm2 V-1 s-1 at room temperatures. This study paves the way for achieving heterogeneous integration of III-V semiconductors and facilitating their application in flexible electronics.
Collapse
Affiliation(s)
- Ziren Xiong
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Yao Wen
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Hao Wang
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Xiaolin Zhang
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Lei Yin
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Ruiqing Cheng
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Yangyuan Tu
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Jun He
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
- Wuhan Institute of Quantum Technology, Wuhan, 430206, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100190, China
- Institute of Semiconductors, Henan Academy of Sciences, Zhengzhou, 450000, China
| |
Collapse
|
3
|
Pan XH, Chen L, Liu DE, Zhang FC, Liu X. Majorana Zero Modes Induced by the Meissner Effect at Small Magnetic Field. PHYSICAL REVIEW LETTERS 2024; 132:036602. [PMID: 38307040 DOI: 10.1103/physrevlett.132.036602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 11/28/2023] [Indexed: 02/04/2024]
Abstract
One key difficulty in realizing Majorana zero modes (MZMs) is the required high magnetic field, which causes serious issues, e.g., shrinks the superconducting gap, reduces topological region, and weakens their robustness against disorders. In this Letter, we propose that the Meissner effect can bring the topological superconducting phase to a superconductor/topological-insulator/superconductor (SC/TI/SC) hybrid system. Remarkably, the required magnetic field strength (<10 mT) to support MZMs has been reduced by several orders of magnitude compared to that (>0.5 T) in the previous schemes. Tuning the phase difference between the top and bottom superconductors can control the number and position of the MZMs. In addition, we account for the electrostatic potential in the superconductor/topological-insulator (SC/TI) interface through the self-consistent Schrödinger-Poisson calculation, which shows the experimental accessibility of our proposal. Our proposal only needs a small magnetic field of less than 10 mT and is robust against the chemical potential fluctuation, which makes the SC/TI/SC hybrid an ideal Majorana platform.
Collapse
Affiliation(s)
- Xiao-Hong Pan
- School of Physics and Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
- Hubei Key Laboratory of Gravitation and Quantum Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
- Wuhan Institute of Quantum Technology, Wuhan, Hubei 430074, China
| | - Li Chen
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, 100084, China
| | - Dong E Liu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, 100084, China
| | - Fu-Chun Zhang
- Kavli Institute for Theoretical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Xin Liu
- School of Physics and Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
- Hubei Key Laboratory of Gravitation and Quantum Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
- Wuhan Institute of Quantum Technology, Wuhan, Hubei 430074, China
| |
Collapse
|
4
|
Hu J, Yu F, Luo A, Pan XH, Zou J, Liu X, Xu G. Chiral Topological Superconductivity in Superconductor-Obstructed Atomic Insulator-Ferromagnetic Insulator Heterostructures. PHYSICAL REVIEW LETTERS 2024; 132:036601. [PMID: 38307042 DOI: 10.1103/physrevlett.132.036601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 12/08/2023] [Indexed: 02/04/2024]
Abstract
Implementing topological superconductivity (TSC) and Majorana states (MSs) is one of the most significant and challenging tasks in both fundamental physics and topological quantum computations. In this work, taking the obstructed atomic insulator (OAI) Nb_{3}Br_{8}, s-wave superconductor (SC) NbSe_{2}, and ferromagnetic insulator (FMI) CrI_{3} as an example, we propose a new setup to realize the 2D chiral TSC and MSs in the SC/OAI/FMI heterostructure, which could avoid the subband problem effectively and has the advantage of huge Rashba spin-orbit coupling. As a result, the TSC phase can be stabilized in a wide region of chemical potential and Zeeman splitting, and four distinct TSC phases with superconducting Chern number N=-1,-2,-3, 3 can be achieved. Moreover, a 2D Bogoliubov-de Gennes Hamiltonian based on the triangular lattice of obstructed Wannier charge centers, combined with the s-wave superconductivity paring and Zeeman splitting, is constructed to understand the whole topological phase diagram analytically. These results expand the application of OAIs and pave a new way to realize the TSC and MSs with unique advantages.
Collapse
Affiliation(s)
- Jingnan Hu
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Fei Yu
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Aiyun Luo
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xiao-Hong Pan
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jinyu Zou
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xin Liu
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
- Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
- Wuhan Institute of Quantum Technology, Wuhan 430206, China
| | - Gang Xu
- Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
- Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
- Wuhan Institute of Quantum Technology, Wuhan 430206, China
| |
Collapse
|
5
|
Khelifi W, Canneson D, Berthe M, Legendre S, Coinon C, Desplanque L, Wallart X, Biadala L, Grandidier B, Capiod P. Ultrahigh vacuum Raman spectroscopy for the preparation of III-V semiconductor surfaces. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:123702. [PMID: 38051176 DOI: 10.1063/5.0152031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 11/09/2023] [Indexed: 12/07/2023]
Abstract
Raman spectroscopy is well-suited for the characterization of semiconductor materials. However, due the weakness of the Raman signal, the studies of thin semiconductor layers in complex environments, such as ultrahigh vacuum, are rather scarce. Here, we have designed a Raman apparatus based on the use of a fiber optic probe, with a lens collecting the backscattered light directly inserted in ultrahigh vacuum. The solution has been tested for the preparation of III-V semiconductor surfaces, which requires the recovery of their atomic reconstruction. The surfaces were either protected with a thin As amorphous layer or covered with a native oxide prior to their treatment. The analysis of the Raman spectra, which was correlated with the study of the surfaces with low temperature scanning tunneling microscopy at the end of the cleaning process, shows the high potential of Raman spectroscopy for monitoring the cleanliness of III-V semiconductor heterostructures in situ.
Collapse
Affiliation(s)
- Wijden Khelifi
- University Lille, CNRS, Centrale Lille, University Polytechnique Hauts-de-France, Junia-ISEN, UMR 8520 - IEMN, F-59000 Lille, France
| | - Damien Canneson
- University Lille, CNRS, Centrale Lille, University Polytechnique Hauts-de-France, Junia-ISEN, UMR 8520 - IEMN, F-59000 Lille, France
- HORIBA France SAS, 455 Avenue Eugène Avinée 59120 Loos, Avenue de la Vauve-Passage Jobin Yvon, 91120 Palaiseau, France
| | - Maxime Berthe
- University Lille, CNRS, Centrale Lille, University Polytechnique Hauts-de-France, Junia-ISEN, UMR 8520 - IEMN, F-59000 Lille, France
| | - Sébastien Legendre
- HORIBA France SAS, 455 Avenue Eugène Avinée 59120 Loos, Avenue de la Vauve-Passage Jobin Yvon, 91120 Palaiseau, France
| | - Christophe Coinon
- University Lille, CNRS, Centrale Lille, University Polytechnique Hauts-de-France, Junia-ISEN, UMR 8520 - IEMN, F-59000 Lille, France
| | - Ludovic Desplanque
- University Lille, CNRS, Centrale Lille, University Polytechnique Hauts-de-France, Junia-ISEN, UMR 8520 - IEMN, F-59000 Lille, France
| | - Xavier Wallart
- University Lille, CNRS, Centrale Lille, University Polytechnique Hauts-de-France, Junia-ISEN, UMR 8520 - IEMN, F-59000 Lille, France
| | - Louis Biadala
- University Lille, CNRS, Centrale Lille, University Polytechnique Hauts-de-France, Junia-ISEN, UMR 8520 - IEMN, F-59000 Lille, France
| | - Bruno Grandidier
- University Lille, CNRS, Centrale Lille, University Polytechnique Hauts-de-France, Junia-ISEN, UMR 8520 - IEMN, F-59000 Lille, France
| | - Pierre Capiod
- University Lille, CNRS, Centrale Lille, University Polytechnique Hauts-de-France, Junia-ISEN, UMR 8520 - IEMN, F-59000 Lille, France
| |
Collapse
|
6
|
Li G, Li M, Zhou X, Gao HJ. Toward large-scale, ordered and tunable Majorana-zero-modes lattice on iron-based superconductors. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2023; 87:016501. [PMID: 37963402 DOI: 10.1088/1361-6633/ad0c5c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 11/14/2023] [Indexed: 11/16/2023]
Abstract
Majorana excitations are the quasiparticle analog of Majorana fermions in solid materials. Typical examples are the Majorana zero modes (MZMs) and the dispersing Majorana modes. When probed by scanning tunneling spectroscopy, the former manifest as a pronounced conductance peak locating precisely at zero-energy, while the latter behaves as constant or slowly varying density of states. The MZMs obey non-abelian statistics and are believed to be building blocks for topological quantum computing, which is highly immune to the environmental noise. Existing MZM platforms include hybrid structures such as topological insulator, semiconducting nanowire or 1D atomic chains on top of a conventional superconductor, and single materials such as the iron-based superconductors (IBSs) and 4Hb-TaS2. Very recently, ordered and tunable MZM lattice has also been realized in IBS LiFeAs, providing a scalable and applicable platform for future topological quantum computation. In this review, we present an overview of the recent local probe studies on MZMs. Classified by the material platforms, we start with the MZMs in the iron-chalcogenide superconductors where FeTe0.55Se0.45and (Li0.84Fe0.16)OHFeSe will be discussed. We then review the Majorana research in the iron-pnictide superconductors as well as other platforms beyond the IBSs. We further review recent works on ordered and tunable MZM lattice, showing that strain is a feasible tool to tune the topological superconductivity. Finally, we give our summary and perspective on future Majorana research.
Collapse
Affiliation(s)
- Geng Li
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- Hefei National Laboratory, Hefei 230088, People's Republic of China
| | - Meng Li
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Xingtai Zhou
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Hong-Jun Gao
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| |
Collapse
|
7
|
Xu R, Xu K, Sun Y, Wen Y, Cheng L, Shen FC, Qian Y. Surface band bending caused by native oxides on solution-processed twinned InSb nanowires with p-type conductivity. NANOSCALE 2023; 15:18473-18480. [PMID: 37941430 DOI: 10.1039/d3nr03924b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
Indium antimonide nanowires (InSb NWs) are attractive building-block candidates for bottom-up construction of high-efficiency electronics and optoelectronics due to their narrow direct band gap, fast room temperature carrier mobilities and small exciton binding energy. However, InSb NWs synthesized by the vapor-liquid-solution (VLS) mechanism generally suffer from an increased carrier and phonon scattering rate, which is thought to be caused by randomly distributed crystal defects along the NW growth direction. In this study, by utilizing the recently developed low-temperature, solution-processed technique, these crystal defects were successfully suppressed by periodically distributed twin planes to form twinned InSb nanowires. Importantly, measurements of the electrical transport properties of field effect transistors (FETs) reveal that the InSb NWs exhibit a hole-dominated conductivity with room temperature mobilities of up to 50.71 cm2 V-1 s-1, which is distinctly contrary to the intrinsic n-type InSb NWs. This observation of n-p switching behavior is probably attributed to the surface band bending effect with regard to the Fermi energy level, which is caused by surface oxide trap states arising from the native-oxide layer at the surface of the InSb NWs. All these results illustrate that the as-prepared colloidal InSb NWs can potentially be used as p-type materials for integration with next-generation nanoscale electronics and optoelectronics via surface engineering.
Collapse
Affiliation(s)
- Rui Xu
- Anhui Laboratory of Clean Energy Materials and Chemistry for Sustainable Conversion of Natural Resources, College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui, 241000, P. R. China.
| | - Kaijia Xu
- Anhui Laboratory of Clean Energy Materials and Chemistry for Sustainable Conversion of Natural Resources, College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui, 241000, P. R. China.
| | - Yingzhi Sun
- Anhui Laboratory of Clean Energy Materials and Chemistry for Sustainable Conversion of Natural Resources, College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui, 241000, P. R. China.
| | - Yan Wen
- Anhui Laboratory of Clean Energy Materials and Chemistry for Sustainable Conversion of Natural Resources, College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui, 241000, P. R. China.
| | - Lanjun Cheng
- School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei, 230009, P. R. China
| | - Feng-Cui Shen
- Anhui Laboratory of Clean Energy Materials and Chemistry for Sustainable Conversion of Natural Resources, College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui, 241000, P. R. China.
| | - Yinyin Qian
- Anhui Laboratory of Clean Energy Materials and Chemistry for Sustainable Conversion of Natural Resources, College of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui, 241000, P. R. China.
| |
Collapse
|
8
|
Yi H, Hu LH, Zhao YF, Zhou LJ, Yan ZJ, Zhang R, Yuan W, Wang Z, Wang K, Hickey DR, Richardella AR, Singleton J, Winter LE, Wu X, Chan MHW, Samarth N, Liu CX, Chang CZ. Dirac-fermion-assisted interfacial superconductivity in epitaxial topological-insulator/iron-chalcogenide heterostructures. Nat Commun 2023; 14:7119. [PMID: 37932274 PMCID: PMC10628154 DOI: 10.1038/s41467-023-42902-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 10/25/2023] [Indexed: 11/08/2023] Open
Abstract
Over the last decade, the possibility of realizing topological superconductivity (TSC) has generated much excitement. TSC can be created in electronic systems where the topological and superconducting orders coexist, motivating the continued exploration of candidate material platforms to this end. Here, we use molecular beam epitaxy (MBE) to synthesize heterostructures that host emergent interfacial superconductivity when a non-superconducting antiferromagnet (FeTe) is interfaced with a topological insulator (TI) (Bi, Sb)2Te3. By performing in-vacuo angle-resolved photoemission spectroscopy (ARPES) and ex-situ electrical transport measurements, we find that the superconducting transition temperature and the upper critical magnetic field are suppressed when the chemical potential approaches the Dirac point. We provide evidence to show that the observed interfacial superconductivity and its chemical potential dependence is the result of the competition between the Ruderman-Kittel-Kasuya-Yosida-type ferromagnetic coupling mediated by Dirac surface states and antiferromagnetic exchange couplings that generate the bicollinear antiferromagnetic order in the FeTe layer.
Collapse
Affiliation(s)
- Hemian Yi
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Lun-Hui Hu
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Yi-Fan Zhao
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Ling-Jie Zhou
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Zi-Jie Yan
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Ruoxi Zhang
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Wei Yuan
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Zihao Wang
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Ke Wang
- Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Danielle Reifsnyder Hickey
- Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Anthony R Richardella
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - John Singleton
- National High Magnetic Field Laboratory, Los Alamos, NM, 87544, USA
| | - Laurel E Winter
- National High Magnetic Field Laboratory, Los Alamos, NM, 87544, USA
| | - Xianxin Wu
- CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Moses H W Chan
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Nitin Samarth
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Chao-Xing Liu
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Cui-Zu Chang
- Department of Physics, The Pennsylvania State University, University Park, PA, 16802, USA.
- Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA.
| |
Collapse
|
9
|
Levajac V, Wang JY, Sfiligoj C, Lemang M, Wolff JC, Bordin A, Badawy G, Gazibegovic S, Bakkers EPAM, Kouwenhoven LP. Subgap spectroscopy along hybrid nanowires by nm-thick tunnel barriers. Nat Commun 2023; 14:6647. [PMID: 37863952 PMCID: PMC10589238 DOI: 10.1038/s41467-023-42422-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 10/11/2023] [Indexed: 10/22/2023] Open
Abstract
Tunneling spectroscopy is widely used to examine the subgap spectra in semiconductor-superconductor nanostructures when searching for Majorana zero modes (MZMs). Typically, semiconductor sections controlled by local gates at the ends of hybrids serve as tunnel barriers. Besides detecting states only at the hybrid ends, such gate-defined tunnel probes can cause the formation of non-topological subgap states that mimic MZMs. Here, we develop an alternative type of tunnel probes to overcome these limitations. After the growth of an InSb-Al hybrid nanowire, a precisely controlled in-situ oxidation of the Al shell is performed to yield a nm-thick AlOx layer. In such thin isolating layer, tunnel probes can be arbitrarily defined at any position along the hybrid nanowire by shadow-wall angle-deposition of metallic leads. In this work, we make multiple tunnel probes along single nanowire hybrids and successfully identify Andreev bound states (ABSs) of various spatial extension residing along the hybrids.
Collapse
Affiliation(s)
- Vukan Levajac
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2628GA, Delft, The Netherlands
| | - Ji-Yin Wang
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2628GA, Delft, The Netherlands.
- Beijing Academy of Quantum Information Sciences, 100193, Beijing, China.
| | - Cristina Sfiligoj
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2628GA, Delft, The Netherlands
| | - Mathilde Lemang
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2628GA, Delft, The Netherlands
| | - Jan Cornelis Wolff
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2628GA, Delft, The Netherlands
| | - Alberto Bordin
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2628GA, Delft, The Netherlands
| | - Ghada Badawy
- Department of Applied Physics, Eindhoven University of Technology, 5600MB, Eindhoven, The Netherlands
| | - Sasa Gazibegovic
- Department of Applied Physics, Eindhoven University of Technology, 5600MB, Eindhoven, The Netherlands
| | - Erik P A M Bakkers
- Department of Applied Physics, Eindhoven University of Technology, 5600MB, Eindhoven, The Netherlands
| | - Leo P Kouwenhoven
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2628GA, Delft, The Netherlands
| |
Collapse
|
10
|
Huguet A, Wrześniewski K, Weymann I. Spin effects on transport and zero-bias anomaly in a hybrid Majorana wire-quantum dot system. Sci Rep 2023; 13:17279. [PMID: 37828058 PMCID: PMC10570336 DOI: 10.1038/s41598-023-44254-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 10/05/2023] [Indexed: 10/14/2023] Open
Abstract
We examine the impact of spin effects on the nonequilibrium transport properties of a nanowire hosting Majorana zero-energy modes at its ends, coupled to a quantum dot junction with ferromagnetic leads. Using the real-time diagrammatic technique, we determine the current, differential conductance and current cross-correlations in the nonlinear response regime. We also explore transport in different magnetic configurations of the system, which can be quantified by the tunnel magnetoresistance. We show that the presence of Majorana quasiparticles gives rise to unique features in all spin-resolved transport characteristics, in particular, to zero-bias anomaly, negative differential conductance, negative tunnel magnetoresistance, and it is also reflected in the current cross-correlations. Moreover, we study the dependence of the zero-bias anomaly on various system parameters and demonstrate its dependence on the magnetic configuration of the system as well as on the degree of spin polarization in the leads. A highly nontrivial behavior is also found for the tunnel magnetoresistance, which exhibits regions of enhanced or negative values-new features resulting from the coupling to Majorana wire.
Collapse
Affiliation(s)
- Alexandre Huguet
- Institute of Spintronics and Quantum Information, Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, 61-614, Poznań, Poland.
- Université de Rennes 1, Campus de Beaulieu, F-35000, Rennes, France.
| | - Kacper Wrześniewski
- Institute of Spintronics and Quantum Information, Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, 61-614, Poznań, Poland.
| | - Ireneusz Weymann
- Institute of Spintronics and Quantum Information, Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, 61-614, Poznań, Poland
| |
Collapse
|
11
|
Chu CG, Chen JJ, Wang AQ, Tan ZB, Li CZ, Li C, Brinkman A, Xiang PZ, Li N, Pan ZC, Lu HZ, Yu D, Liao ZM. Broad and colossal edge supercurrent in Dirac semimetal Cd 3As 2 Josephson junctions. Nat Commun 2023; 14:6162. [PMID: 37788988 PMCID: PMC10547728 DOI: 10.1038/s41467-023-41815-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 09/12/2023] [Indexed: 10/05/2023] Open
Abstract
Edge supercurrent has attracted great interest recently due to its crucial role in achieving and manipulating topological superconducting states. Proximity-induced superconductivity has been realized in quantum Hall and quantum spin Hall edge states, as well as in higher-order topological hinge states. Non-Hermitian skin effect, the aggregation of non-Bloch eigenstates at open boundaries, promises an abnormal edge channel. Here we report the observation of broad edge supercurrent in Dirac semimetal Cd3As2-based Josephson junctions. The as-grown Cd3As2 nanoplates are electron-doped by intrinsic defects, which enhance the non-Hermitian perturbations. The superconducting quantum interference indicates edge supercurrent with a width of ~1.6 μm and a magnitude of ~1 μA at 10 mK. The wide and large edge supercurrent is inaccessible for a conventional edge system and suggests the presence of non-Hermitian skin effect. A supercurrent nonlocality is also observed. The interplay between band topology and non-Hermiticity is beneficial for exploiting exotic topological matter.
Collapse
Affiliation(s)
- Chun-Guang Chu
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, 100871, Beijing, China
| | - Jing-Jing Chen
- Shenzhen Institute for Quantum Science and Engineering, Department of Physics, Southern University of Science and Technology, 518055, Shenzhen, China
- International Quantum Academy, 518048, Shenzhen, China
| | - An-Qi Wang
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, 100871, Beijing, China.
| | - Zhen-Bing Tan
- Shenzhen Institute for Quantum Science and Engineering, Department of Physics, Southern University of Science and Technology, 518055, Shenzhen, China.
- International Quantum Academy, 518048, Shenzhen, China.
| | - Cai-Zhen Li
- Shenzhen Institute for Quantum Science and Engineering, Department of Physics, Southern University of Science and Technology, 518055, Shenzhen, China
- International Quantum Academy, 518048, Shenzhen, China
| | - Chuan Li
- MESA+ Institute for Nanotechnology, University of Twente, 7500 AE, Enschede, The Netherlands
| | - Alexander Brinkman
- MESA+ Institute for Nanotechnology, University of Twente, 7500 AE, Enschede, The Netherlands
| | - Peng-Zhan Xiang
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, 100871, Beijing, China
| | - Na Li
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, 100871, Beijing, China
| | - Zhen-Cun Pan
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, 100871, Beijing, China
| | - Hai-Zhou Lu
- Shenzhen Institute for Quantum Science and Engineering, Department of Physics, Southern University of Science and Technology, 518055, Shenzhen, China
| | - Dapeng Yu
- Shenzhen Institute for Quantum Science and Engineering, Department of Physics, Southern University of Science and Technology, 518055, Shenzhen, China
- International Quantum Academy, 518048, Shenzhen, China
- Hefei National Laboratory, 230088, Hefei, China
| | - Zhi-Min Liao
- State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, 100871, Beijing, China.
- Hefei National Laboratory, 230088, Hefei, China.
| |
Collapse
|
12
|
Zhang F, Gu J, Quan HT. Full counting statistics, fluctuation relations, and linear response properties in a one-dimensional Kitaev chain. Phys Rev E 2023; 108:024110. [PMID: 37723789 DOI: 10.1103/physreve.108.024110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 07/10/2023] [Indexed: 09/20/2023]
Abstract
We analytically calculate the cumulant generating function of energy and particle transport in an open one-dimensional Kitaev chain at finite temperature by utilizing the Keldysh technique. The joint distribution of particle and energy currents satisfies different fluctuation relations in different regions of the parameter space as a result of U(1) symmetry breaking and energy conservation. Furthermore, we investigate the linear response behavior of the Kitaev chain within the framework of three-terminal systems, deriving the expressions for the Seebeck coefficient and thermal conductance. Notably, we observe a pronounced peak in the thermal conductance near the phase transition point, in agreement with previous predictions. Additionally, we prove that the peak value saturates at half of the thermal conductance quantum for finite-length chains at the zero temperature limit.
Collapse
Affiliation(s)
- Fan Zhang
- School of Physics, Peking University, Beijing 100871, China
| | - Jiayin Gu
- School of Physics and Technology, Nanjing Normal University, Nanjing 210023, People's Republic of China
| | - H T Quan
- School of Physics, Peking University, Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
- Frontiers Science Center for Nano-optoelectronics, Peking University, Beijing, 100871, China
| |
Collapse
|
13
|
Yan S, Su H, Pan D, Li W, Lyu Z, Chen M, Wu X, Lu L, Zhao J, Wang JY, Xu H. Supercurrent, Multiple Andreev Reflections and Shapiro Steps in InAs Nanosheet Josephson Junctions. NANO LETTERS 2023. [PMID: 37450769 DOI: 10.1021/acs.nanolett.3c01450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
We report an experimental study of proximity induced superconductivity in planar Josephson junction devices made from free-standing InAs nanosheets. The nanosheets are grown by molecular beam epitaxy, and the Josephson junction devices are fabricated by directly contacting the nanosheets with superconductor Al electrodes. The fabricated devices are explored by low-temperature carrier transport measurements. The measurements show that the devices exhibit a gate-tunable supercurrent, multiple Andreev reflections, and a good quality superconductor-semiconductor interface. The superconducting characteristics of the Josephson junctions are investigated at different magnetic fields and temperatures and are analyzed based on the Bardeen-Cooper-Schrieffer (BCS) theory. The measurements of the ac Josephson effect are also conducted under microwave radiations with different radiation powers and frequencies, and integer Shapiro steps are observed. Our work demonstrates that InAs nanosheet based hybrid devices are desired systems for investigating the forefront of physics, such as two-dimensional topological superconductivity.
Collapse
Affiliation(s)
- Shili Yan
- Beijing Academy of Quantum Information Sciences, 100193 Beijing, China
| | - Haitian Su
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, and School of Electronics, Peking University, Beijing 100871, China
- Institute of Condensed Matter and Material Physics, School of Physics, Peking University, Beijing 100871, China
| | - Dong Pan
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083, China
| | - Weijie Li
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, and School of Electronics, Peking University, Beijing 100871, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Zhaozheng Lyu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Mo Chen
- Beijing Academy of Quantum Information Sciences, 100193 Beijing, China
| | - Xingjun Wu
- Beijing Academy of Quantum Information Sciences, 100193 Beijing, China
| | - Li Lu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences; School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Jianhua Zhao
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083, China
| | - Ji-Yin Wang
- Beijing Academy of Quantum Information Sciences, 100193 Beijing, China
| | - Hongqi Xu
- Beijing Academy of Quantum Information Sciences, 100193 Beijing, China
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, and School of Electronics, Peking University, Beijing 100871, China
| |
Collapse
|
14
|
Hess R, Legg HF, Loss D, Klinovaja J. Trivial Andreev Band Mimicking Topological Bulk Gap Reopening in the Nonlocal Conductance of Long Rashba Nanowires. PHYSICAL REVIEW LETTERS 2023; 130:207001. [PMID: 37267549 DOI: 10.1103/physrevlett.130.207001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 02/07/2023] [Accepted: 04/04/2023] [Indexed: 06/04/2023]
Abstract
We consider a one-dimensional Rashba nanowire in which multiple Andreev bound states in the bulk of the nanowire form an Andreev band. We show that, under certain circumstances, this trivial Andreev band can produce an apparent closing and reopening signature of the bulk band gap in the nonlocal conductance of the nanowire. Furthermore, we show that the existence of the trivial bulk reopening signature in nonlocal conductance is essentially unaffected by the additional presence of trivial zero-bias peaks in the local conductance at either end of the nanowire. The simultaneous occurrence of a trivial bulk reopening signature and zero-bias peaks mimics the basic features required to pass the so-called "topological gap protocol." Our results therefore provide a topologically trivial minimal model by which the applicability of this protocol can be benchmarked.
Collapse
Affiliation(s)
- Richard Hess
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| | - Henry F Legg
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| | - Daniel Loss
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| | - Jelena Klinovaja
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| |
Collapse
|
15
|
Thamm M, Rosenow B. Machine Learning Optimization of Majorana Hybrid Nanowires. PHYSICAL REVIEW LETTERS 2023; 130:116202. [PMID: 37001061 DOI: 10.1103/physrevlett.130.116202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 02/21/2023] [Indexed: 06/19/2023]
Abstract
As the complexity of quantum systems such as quantum bit arrays increases, efforts to automate expensive tuning are increasingly worthwhile. We investigate machine learning based tuning of gate arrays using the covariance matrix adaptation evolution strategy algorithm for the case study of Majorana wires with strong disorder. We find that the algorithm is able to efficiently improve the topological signatures, learn intrinsic disorder profiles, and completely eliminate disorder effects. For example, with only 20 gates, it is possible to fully recover Majorana zero modes destroyed by disorder by optimizing gate voltages.
Collapse
Affiliation(s)
- Matthias Thamm
- Institut für Theoretische Physik, Universität Leipzig, Brüderstrasse 16, 04103 Leipzig, Germany
| | - Bernd Rosenow
- Institut für Theoretische Physik, Universität Leipzig, Brüderstrasse 16, 04103 Leipzig, Germany
| |
Collapse
|
16
|
Hu LH, Wu X, Liu CX, Zhang RX. Competing Vortex Topologies in Iron-Based Superconductors. PHYSICAL REVIEW LETTERS 2022; 129:277001. [PMID: 36638298 DOI: 10.1103/physrevlett.129.277001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
In this Letter, we establish a new theoretical paradigm for vortex Majorana physics in the recently discovered topological iron-based superconductors (TFeSCs). While TFeSCs are widely accepted as an exemplar of topological insulators (TIs) with intrinsic s-wave superconductivity, our theory implies that such a common belief could be oversimplified. Our main finding is that the normal-state bulk Dirac nodes, usually ignored in TI-based vortex Majorana theories for TFeSCs, will play a key role of determining the vortex state topology. In particular, the interplay between TI and Dirac nodal bands will lead to multiple competing topological phases for a superconducting vortex line in TFeSCs, including an unprecedented hybrid topological vortex state that carries both Majorana bound states and a gapless dispersion. Remarkably, this exotic hybrid vortex phase generally exists in the vortex phase diagram for our minimal model for TFeSCs and is directly relevant to TFeSC candidates such as LiFeAs. When the fourfold rotation symmetry is broken by vortex-line tilting or curving, the hybrid vortex gets topologically trivialized and becomes Majorana free, which could explain the puzzle of ubiquitous trivial vortices observed in LiFeAs. The origin of the Majorana signal in other TFeSC candidates such as FeTe_{x}Se_{1-x} and CaKFe_{4}As_{4} is also interpreted within our theory framework. Our theory sheds new light on theoretically understanding and experimentally engineering Majorana physics in high-temperature iron-based systems.
Collapse
Affiliation(s)
- Lun-Hui Hu
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996, USA
- Institute for Advanced Materials and Manufacturing, The University of Tennessee, Knoxville, Tennessee 37920, USA
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Xianxin Wu
- CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, China
- Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
| | - Chao-Xing Liu
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Rui-Xing Zhang
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996, USA
- Institute for Advanced Materials and Manufacturing, The University of Tennessee, Knoxville, Tennessee 37920, USA
- Department of Materials Science and Engineering, The University of Tennessee, Knoxville, Tennessee 37996, USA
| |
Collapse
|
17
|
Baldelli N, Bhattacharya U, González-Cuadra D, Lewenstein M, Graß T. Detecting Majorana Zero Modes via Strong Field Dynamics. ACS OMEGA 2022; 7:47424-47430. [PMID: 36570179 PMCID: PMC9773937 DOI: 10.1021/acsomega.2c07169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 11/24/2022] [Indexed: 06/17/2023]
Abstract
We propose a protocol to detect topological phase transitions of one-dimensional p-wave superconductors from their harmonic emission spectra in strong fields. Specifically, we identify spectral features due to radiating edge modes, which characterize the spectrum and the density of states in the topological phase and are absent in the trivial phase. These features allow us to define a measurable signature, obtained from emission measurements, that unambiguously differentiates between the two phases. Local probing provides insight into the localized and topologically protected nature of the modes. The presented results establish that high-harmonic spectroscopy can be used as an all-optical tool for the detection of Majorana zero modes.
Collapse
Affiliation(s)
- Niccolò Baldelli
- Institut
de Ciencies Fotoniques (ICFO), The Barcelona Institute of Science
and Technology, 08860Castelldefels, Barcelona, Spain
| | - Utso Bhattacharya
- Institut
de Ciencies Fotoniques (ICFO), The Barcelona Institute of Science
and Technology, 08860Castelldefels, Barcelona, Spain
| | - Daniel González-Cuadra
- Institut
de Ciencies Fotoniques (ICFO), The Barcelona Institute of Science
and Technology, 08860Castelldefels, Barcelona, Spain
- Institute
for Theoretical Physics, University of Innsbruck, 6020Innsbruck, Austria
- Institute
for Quantum Optics and Quantum Information, Austrian Academy of Sciences, 6020Innsbruck, Austria
| | - Maciej Lewenstein
- Institut
de Ciencies Fotoniques (ICFO), The Barcelona Institute of Science
and Technology, 08860Castelldefels, Barcelona, Spain
- Institución
Catalana de Investigación y Esteudios Avanzados (ICREA), Pg. Lluis Companys 23, 08010Barcelona, Barcelona, Spain
| | - Tobias Graß
- Institut
de Ciencies Fotoniques (ICFO), The Barcelona Institute of Science
and Technology, 08860Castelldefels, Barcelona, Spain
- Donostia
International Physics Center (DIPC), Paseo Manuel de Lardizábal 4, 20018San Sebastián, Gipuzkoa, Spain
- Ikerbasque, Maria Diaz de Haro 3, 48013Bilbao, Biscay, Spain
| |
Collapse
|
18
|
Wang Z, Feng JJ, Huang Z, Niu Q. Transport Theory for Topological Josephson Junctions with a Majorana Qubit. PHYSICAL REVIEW LETTERS 2022; 129:257001. [PMID: 36608237 DOI: 10.1103/physrevlett.129.257001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 11/15/2022] [Indexed: 06/17/2023]
Abstract
We construct a semiclassical theory for the transport of topological Josephson junctions starting from a microscopic Hamiltonian that comprehensively includes the interplay among the Majorana qubit, the Josephson phase, and the dissipation process. With the path integral approach, we derive a set of semiclassical equations of motion that can be used to calculate the time evolution of the Josephson phase and the Majorana qubit. In the equations we reveal rich dynamical phenomena such as the qubit-induced charge pumping, the effective spin-orbit torque, and the Gilbert damping. We demonstrate the influence of these dynamical phenomena on the transport signatures of the junction. We apply the theory to study the Shapiro steps of the junction, and find the suppression of the first Shapiro step due to the dynamical feedback of the Majorana qubit.
Collapse
Affiliation(s)
- Zhi Wang
- School of Physics, Sun Yat-sen University, Guangzhou 510275, China
- Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, Sun Yat-sen University, Guangzhou 510275, China
| | - Jia-Jin Feng
- International Center for Quantum Materials, Peking University, Beijing 100871, China
| | - Zhao Huang
- Texas Center for Superconductivity, University of Houston, Houston, Texas 77204, USA
| | - Qian Niu
- School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China
| |
Collapse
|
19
|
Exactly solving the Kitaev chain and generating Majorana-zero-modes out of noisy qubits. Sci Rep 2022; 12:19882. [DOI: 10.1038/s41598-022-24341-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 11/14/2022] [Indexed: 11/19/2022] Open
Abstract
AbstractMajorana-zero-modes (MZMs) were predicted to exist as edge states of a physical system called the Kitaev chain. MZMs should host particles that are their own antiparticles and could be used as a basis for a qubit which is robust-to-noise. However, all attempts to prove their existence gave inconclusive results. Here, the Kitaev chain is exactly solved with a quantum computing methodology and properties of MZMs are probed by generating eigenstates of the Kitev Hamiltonian on 3 noisy qubits of a publicly available quantum computer. After an ontological elaboration I show that two eigenstates of the Kitaev Hamiltonian exhibit eight signatures attributed to MZMs. The results presented here are a most comprehensive set of validations of MZMs ever conducted in an actual physical system. Furthermore, the findings of this manuscript are easily reproducible for any user of publicly available quantum computers, solving another important problem of research with MZMs—the result reproducibility crisis.
Collapse
|
20
|
Hao Y, Zhang G, Liu D, Liu DE. Anomalous universal conductance as a hallmark of non-locality in a Majorana-hosted superconducting island. Nat Commun 2022; 13:6699. [PMID: 36335121 PMCID: PMC9637197 DOI: 10.1038/s41467-022-34437-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 10/25/2022] [Indexed: 11/07/2022] Open
Abstract
The non-local feature of topological states of matter is the key for the topological protection of quantum information and enables robust non-local manipulation in quantum information. Here we propose to manifest the non-local feature of a Majorana-hosted superconducting island by measuring the temperature dependence of Coulomb blockade peak conductance in different regimes. In the low-temperature regime, we discover a coherent double Majorana-assisted teleportation (MT) process, where any independent tunneling process always involves two coherent non-local MTs; and we also find an anomalous universal scaling behavior, i.e., a crossover from a \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${[\max (T,eV)]}^{6}$$\end{document}[max(T,eV)]6 power-law to a \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${[\max (T,eV)]}^{3}$$\end{document}[max(T,eV)]3 power-law conductance behavior when energy scale increases — in stark contrast to the usual exponential suppression due to certain local transport. In the high-temperature regime, the conductance is instead proportional to the temperature inverse, indicating a non-monotonic temperature-dependence of the conductance. Both the anomalous power law and non-monotonic temperature-dependence of the conductance can be distinguished from the conductance peak in the traditional Coulomb block, and therefore, together serve as a hallmark for the non-local feature in the Majorana-hosted superconducting island. The ability to detect the non-local nature of topological states in electron transport is highly desirable for topological quantum computation. Hao et al. propose a two-terminal transport scheme to detect the non-locality of a topological superconducting island via anomalous scaling of the tunnelling conductance.
Collapse
Affiliation(s)
- Yiru Hao
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, 100084, Beijing, China.,Frontier Science Center for Quantum Information, 100184, Beijing, China
| | - Gu Zhang
- Beijing Academy of Quantum Information Sciences, 100193, Beijing, China
| | - Donghao Liu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, 100084, Beijing, China
| | - Dong E Liu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, 100084, Beijing, China. .,Frontier Science Center for Quantum Information, 100184, Beijing, China. .,Beijing Academy of Quantum Information Sciences, 100193, Beijing, China.
| |
Collapse
|
21
|
Mazur GP, van Loo N, Wang JY, Dvir T, Wang G, Khindanov A, Korneychuk S, Borsoi F, Dekker RC, Badawy G, Vinke P, Gazibegovic S, Bakkers EPAM, Pérez MQ, Heedt S, Kouwenhoven LP. Spin-Mixing Enhanced Proximity Effect in Aluminum-Based Superconductor-Semiconductor Hybrids. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2202034. [PMID: 35680622 DOI: 10.1002/adma.202202034] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 04/25/2022] [Indexed: 06/15/2023]
Abstract
In superconducting quantum circuits, aluminum is one of the most widely used materials. It is currently also the superconductor of choice for the development of topological qubits. However, aluminum-based devices suffer from poor magnetic field compatibility. Herein, this limitation is resolved by showing that adatoms of heavy elements (e.g., platinum) increase the critical field of thin aluminum films by more than a factor of two. Using tunnel junctions, it is shown that the increased field resilience originates from spin-orbit scattering introduced by Pt. This property is exploited in the context of the superconducting proximity effect in semiconductor-superconductor hybrids, where it is shown that InSb nanowires strongly coupled to Al/Pt films can maintain superconductivity up to 7 T. The two-electron charging effect is shown to be robust against the presence of heavy adatoms. Additionally, non-local spectroscopy is used in a three-terminal geometry to probe the bulk of hybrid devices, showing that it remains free of sub-gap states. Finally, it is demonstrated that proximitized semiconductor states maintain their ability to Zeeman-split in an applied magnetic field. Combined with the chemical stability and well-known fabrication routes of aluminum, Al/Pt emerges as the natural successor to Al-based systems and is a compelling alternative to other superconductors, whenever high-field resilience is required.
Collapse
Affiliation(s)
- Grzegorz P Mazur
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| | - Nick van Loo
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| | - Ji-Yin Wang
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| | - Tom Dvir
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| | - Guanzhong Wang
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| | - Aleksei Khindanov
- Department of Physics, University of California, Santa Barbara, CA, 93106, USA
| | - Svetlana Korneychuk
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| | - Francesco Borsoi
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| | - Robin C Dekker
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| | - Ghada Badawy
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, 5600 MB, The Netherlands
| | - Peter Vinke
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| | - Sasa Gazibegovic
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, 5600 MB, The Netherlands
| | - Erik P A M Bakkers
- Department of Applied Physics, Eindhoven University of Technology, Eindhoven, 5600 MB, The Netherlands
| | - Marina Quintero- Pérez
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
- Netherlands Organisation for Applied Scientific Research (TNO), Delft, 2600 AD, The Netherlands
| | - Sebastian Heedt
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| | - Leo P Kouwenhoven
- QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, 2600 GA, The Netherlands
| |
Collapse
|
22
|
Liu L, Sun S, Huo Y, Li S, Han T. Current through a hybrid four-terminal Josephson junction with Majorana nanowires. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:395302. [PMID: 35835089 DOI: 10.1088/1361-648x/ac8131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 07/14/2022] [Indexed: 06/15/2023]
Abstract
We investigate the current through a hybrid four-terminal Josephson junction with semiconductor nanowires, in which the junction is connected with two superconducting electrodes and two normal electrodes. The semiconductor nanowire, which is subject to an external magnetic field with Rashba spin-orbit coupling and proximity-induced superconductivity, can host Majorana bound states. When all the nanowires lie in topological nontrivial region, a 4π-periodic current can be observed through the normal terminal and a 2π-periodic current through the superconducting terminal. When a rotating magnetic field is applied to the junction, the supercurrent through different terminals varies with the variation of the magnetic field direction. Only when the magnetic field is applied at certain angles, we find that the 4π-periodic current will appear through the normal terminal.
Collapse
Affiliation(s)
- Long Liu
- Hebei College of Industry and Technology, Shijiazhuang, Hebei, 050091, People's Republic of China
| | - Sutao Sun
- School of Mathmatics and Science, Hebei GEO University, Shijiazhuang 050031, People's Republic of China
| | - Yunchang Huo
- Hebei College of Industry and Technology, Shijiazhuang, Hebei, 050091, People's Republic of China
| | - Shuang Li
- Hebei College of Industry and Technology, Shijiazhuang, Hebei, 050091, People's Republic of China
| | - Tiwen Han
- Hebei College of Industry and Technology, Shijiazhuang, Hebei, 050091, People's Republic of China
| |
Collapse
|
23
|
Fan F, Chen Y, Pan D, Zhao J, Xu HQ. Electrically tunable spin-orbit interaction in an InAs nanosheet. NANOSCALE ADVANCES 2022; 4:2642-2648. [PMID: 36132279 PMCID: PMC9417834 DOI: 10.1039/d2na00143h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
We report an experimental study of the spin-orbit interaction (SOI) in an epitaxially grown free-standing InAs nanosheet in a dual-gate field-effect device. Gate-transfer characteristic measurements show that independent tuning of the carrier density in the nanosheet and the potential difference across the nanosheet can be efficiently achieved with the use of a dual gate. The quantum transport characteristics of the InAs nanosheet are investigated by magnetoconductance measurements at low temperatures. It is shown that the electron transport in the nanosheet can be tuned from the weak antilocalization to the weak localization and then back to the weak antilocalization regime with a voltage applied over the dual gate without a change in the carrier density. The spin-orbit length extracted from the magnetoconductance measurements at a constant carrier density exhibits a peak value at which the SOI of the Rashba type is suppressed and the spin relaxation due to the presence of an SOI of the Dresselhaus type in the nanosheet can be revealed. Energy band diagram simulations have also been carried out for the device under the experimental conditions and the physical insights into the experimental observations have been discussed in light of the results of simulations.
Collapse
Affiliation(s)
- Furong Fan
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University Beijing 100871 China
| | - Yuanjie Chen
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University Beijing 100871 China
| | - Dong Pan
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences P.O. Box 912 Beijing 100083 China
| | - Jianhua Zhao
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences P.O. Box 912 Beijing 100083 China
| | - H Q Xu
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University Beijing 100871 China
- Beijing Academy of Quantum Information Sciences Beijing 100193 China
| |
Collapse
|
24
|
Sato Y, Ueda K, Takeshige Y, Kamata H, Li K, Samuelson L, Xu HQ, Matsuo S, Tarucha S. Quasiparticle Trapping at Vortices Producing Josephson Supercurrent Enhancement. PHYSICAL REVIEW LETTERS 2022; 128:207001. [PMID: 35657870 DOI: 10.1103/physrevlett.128.207001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 04/04/2022] [Indexed: 06/15/2023]
Abstract
The Josephson junction of a strong spin-orbit material under a magnetic field is a promising Majorana fermion candidate. Supercurrent enhancement by a magnetic field has been observed in the InAs nanowire Josephson junctions and assigned to a topological transition. In this work we observe a similar phenomenon but discuss the nontopological origin by considering the trapping of quasiparticles by vortices that penetrate the superconductor under a finite magnetic field. This assignment is supported by the observed hysteresis of the switching current when sweeping up and down the magnetic field. Our experiment shows the importance of quasiparticles in superconducting devices with a magnetic field, which can provide important insights for the design of qubits using superconductors.
Collapse
Affiliation(s)
- Yosuke Sato
- Department of Applied Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
- Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Kento Ueda
- Department of Applied Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yuusuke Takeshige
- Department of Applied Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hiroshi Kamata
- Laboratoire de Physique de l'École Normale Supérieure, ENS, PSL Research University, CNRS, Sorbonne Université, Université Paris Diderot, Sorbonne Paris Cité, 24 rue Lhomond, 75231 Paris Cedex 05, France
| | - Kan Li
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices and School of Electronics, Peking University, Beijing 100871, China
| | - Lars Samuelson
- Division of Solid State Physics and NanoLund, Lund University, Box 118, SE-221 00 Lund, Sweden
- Department of Electrical and Electronic Engineering, Southern University of Science and Technology, 1088 Xueyuan Blvd, Nanshan, Shenzhen, Guangdong 518055, China
| | - H Q Xu
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices and School of Electronics, Peking University, Beijing 100871, China
- Division of Solid State Physics and NanoLund, Lund University, Box 118, SE-221 00 Lund, Sweden
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Sadashige Matsuo
- Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Seigo Tarucha
- Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- RIKEN Center for Quantum Computing, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| |
Collapse
|
25
|
Su ZC, Li YH, Lin CF. Mid-Infrared Response from Cr/n-Si Schottky Junction with an Ultra-Thin Cr Metal. NANOMATERIALS 2022; 12:nano12101750. [PMID: 35630971 PMCID: PMC9143420 DOI: 10.3390/nano12101750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 05/09/2022] [Accepted: 05/18/2022] [Indexed: 12/10/2022]
Abstract
Infrared detection technology has been widely applied in many areas. Unlike internal photoemission and the photoelectric mechanism, which are limited by the interface barrier height and material bandgap, the research of the hot carrier effect from nanometer thickness of metal could surpass the capability of silicon-based Schottky devices to detect mid-infrared and even far-infrared. In this work, we investigate the effects of physical characteristics of Cr nanometal surfaces and metal/silicon interfaces on hot carrier optical detection. Based on the results of scanning electron microscopy, atomic force microscopy, and X-ray diffraction analysis, the hot carrier effect and the variation of optical response intensity are found to depend highly on the physical properties of metal surfaces, such as surface coverage, metal thickness, and internal stress. Since the contact layer formed by Cr and Si is the main role of infrared light detection in the experiment, the higher the metal coverage, the higher the optical response. Additionally, a thicker metal surface makes the hot carriers take a longer time to convert into current signals after generation, leading to signal degradation due to the short lifetime of the hot carriers. Furthermore, the film with the best hot carrier effect induced in the Cr/Si structure is able to detect an infrared signal up to 4.2 μm. Additionally, it has a 229 times improvement in the signal-to-noise ratio (SNR) for a single band compared with ones with less favorable conditions.
Collapse
Affiliation(s)
- Zih-Chun Su
- Graduate Institute of Photonics and Optoelectronics, The Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan; (Z.-C.S.); (Y.-H.L.)
| | - Yu-Hao Li
- Graduate Institute of Photonics and Optoelectronics, The Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan; (Z.-C.S.); (Y.-H.L.)
| | - Ching-Fuh Lin
- Graduate Institute of Photonics and Optoelectronics, The Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan; (Z.-C.S.); (Y.-H.L.)
- Graduate Institute of Electronics Engineering, The Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan
- Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan
- Correspondence:
| |
Collapse
|
26
|
Zhang L, Chen Y, Pan D, Huang S, Zhao J, Xu HQ. Fabrication and characterization of InSb nanosheet/hBN/graphite heterostructure devices. NANOTECHNOLOGY 2022; 33:325303. [PMID: 35504264 DOI: 10.1088/1361-6528/ac6c34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 04/29/2022] [Indexed: 06/14/2023]
Abstract
Semiconductor InSb nanosheet/hexagonal boron nitride (hBN)/graphite trilayers are fabricated, and single- and double-gate devices made from the trilayers are realized and characterized. The InSb nanosheets employed in the trilayer devices are epitaxially grown, free-standing, zincblende crystals and are in micrometer lateral sizes. The hBN and graphite flakes are obtained by exfoliation. Each trilayer is made by successively stacking an InSb nanosheet on an hBN flake and on a graphite flake using a home-made alignment stacking/transfer setup. The fabricated single- and double-gate devices are characterized by electrical and/or magnetotransport measurements. In all these devices, the graphite and hBN flakes are employed as the bottom gates and the gate dielectrics. The measurements of a fabricated single bottom-gate field-effect device show that the InSb nanosheet in the device has an electron field-effect mobility of ∼7300 cm2V-1s-1and a low gate hysteresis of ∼0.05 V at 1.9 K. The measurements of a double-gate Hall-bar device show that both the top and the bottom gate exhibit strong capacitive couplings to the InSb nanosheet channel and can thus tune the nanosheet channel conduction effectively. The electron Hall mobility in the InSb nanosheet of the Hall-bar device is extracted to be larger than 1.1 × 104cm2V-1s-1at a sheet electron density of ∼6.1 × 1011cm-2and 1.9 K and, thus, the device exhibits well-defined Shubnikov-de Haas oscillations.
Collapse
Affiliation(s)
- Li Zhang
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, and School of Electronics, Peking University, Beijing 100871, People's Republic of China
| | - Yuanjie Chen
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, and School of Electronics, Peking University, Beijing 100871, People's Republic of China
| | - Dong Pan
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, PO Box 912, Beijing 100083, People's Republic of China
| | - Shaoyun Huang
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, and School of Electronics, Peking University, Beijing 100871, People's Republic of China
| | - Jianhua Zhao
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, PO Box 912, Beijing 100083, People's Republic of China
| | - H Q Xu
- Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices, and School of Electronics, Peking University, Beijing 100871, People's Republic of China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, People's Republic of China
| |
Collapse
|
27
|
Li C, Luo XJ, Chen L, Liu DE, Zhang FC, Liu X. Controllable majorana vortex states in iron-based superconducting nanowires. Natl Sci Rev 2022; 9:nwac095. [PMID: 36196249 PMCID: PMC9521342 DOI: 10.1093/nsr/nwac095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 04/15/2022] [Accepted: 04/15/2022] [Indexed: 11/14/2022] Open
Abstract
To reveal the non-Abelian braiding statistics of Majorana zero modes (MZMs), it is crucial to design a Majorana platform, in which MZMs can be easily manipulated in a broad topological nontrivial parameter space. This is also an essential step to confirm their existence. In this study, we propose an iron-based superconducting nanowire system with Majorana vortex states to satisfy desirable conditions. This system has a radius-induced topological phase transition, giving a lower bound for the nanowire radius. In the topological phase, the iron-based superconducting nanowires have only one pair of MZMs over a wide range of radii, chemical potential and external magnetic fields. The wave function of MZMs has a sizable distribution at the side edge of the nanowires. This property enables the control of the interaction of MZMs in neighboring vortex nanowires and paves the way for Majorana fusion and braiding.
Collapse
Affiliation(s)
- Chuang Li
- School of Physics and Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
- Wuhan National High Magnetic Field Center and Hubei Key Laboratory of Gravitation and Quantum Physics, Wuhan, 430074, China
| | - Xun-Jiang Luo
- School of Physics and Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
- Wuhan National High Magnetic Field Center and Hubei Key Laboratory of Gravitation and Quantum Physics, Wuhan, 430074, China
| | - Li Chen
- School of Physics and Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
- Wuhan National High Magnetic Field Center and Hubei Key Laboratory of Gravitation and Quantum Physics, Wuhan, 430074, China
| | - Dong E Liu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing, 100084, China
| | - Fu-Chun Zhang
- Kavli Institute for Theoretical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Xin Liu
- School of Physics and Institute for Quantum Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
- Wuhan National High Magnetic Field Center and Hubei Key Laboratory of Gravitation and Quantum Physics, Wuhan, 430074, China
| |
Collapse
|
28
|
McLauchlan CK, Béri B. Fermion-Parity-Based Computation and Its Majorana-Zero-Mode Implementation. PHYSICAL REVIEW LETTERS 2022; 128:180504. [PMID: 35594115 DOI: 10.1103/physrevlett.128.180504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 03/29/2022] [Indexed: 06/15/2023]
Abstract
Majorana zero modes (MZMs) promise a platform for topologically protected fermionic quantum computation. However, creating multiple MZMs and generating (directly or via measurements) the requisite transformations (e.g., braids) pose significant challenges. We introduce fermion-parity-based computation (FPBC): a measurement-based scheme, modeled on Pauli-based computation, that uses efficient classical processing to virtually increase the number of available MZMs and which, given magic state inputs, operates without transformations. FPBC requires all MZM parities to be measurable, but this conflicts with constraints in proposed MZM hardware. We thus introduce a design in which all parities are directly measurable and which is hence well suited for FPBC. While developing FPBC, we identify the "logical braid group" as the fermionic analog of the Clifford group.
Collapse
Affiliation(s)
| | - Benjamin Béri
- DAMTP, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, United Kingdom
- T.C.M. Group, Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| |
Collapse
|
29
|
Zhou T, Dartiailh MC, Sardashti K, Han JE, Matos-Abiague A, Shabani J, Žutić I. Fusion of Majorana bound states with mini-gate control in two-dimensional systems. Nat Commun 2022; 13:1738. [PMID: 35365644 PMCID: PMC8976011 DOI: 10.1038/s41467-022-29463-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 03/16/2022] [Indexed: 11/09/2022] Open
Abstract
A hallmark of topological superconductivity is the non-Abelian statistics of Majorana bound states (MBS), its chargeless zero-energy emergent quasiparticles. The resulting fractionalization of a single electron, stored nonlocally as a two spatially-separated MBS, provides a powerful platform for implementing fault-tolerant topological quantum computing. However, despite intensive efforts, experimental support for MBS remains indirect and does not probe their non-Abelian statistics. Here we propose how to overcome this obstacle in mini-gate controlled planar Josephson junctions (JJs) and demonstrate non-Abelian statistics through MBS fusion, detected by charge sensing using a quantum point contact, based on dynamical simulations. The feasibility of preparing, manipulating, and fusing MBS in two-dimensional (2D) systems is supported in our experiments which demonstrate the gate control of topological transition and superconducting properties with five mini gates in InAs/Al-based JJs. While we focus on this well-established platform, where the topological superconductivity was already experimentally detected, our proposal to identify elusive non-Abelian statistics motivates also further MBS studies in other gate-controlled 2D systems.
Collapse
Affiliation(s)
- Tong Zhou
- Department of Physics, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA.
| | - Matthieu C Dartiailh
- Center for Quantum Phenomena, Department of Physics, New York University, New York, NY, 10003, USA
| | - Kasra Sardashti
- Center for Quantum Phenomena, Department of Physics, New York University, New York, NY, 10003, USA
| | - Jong E Han
- Department of Physics, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA
| | - Alex Matos-Abiague
- Department of Physics and Astronomy, Wayne State University, Detroit, MI, 48201, USA
| | - Javad Shabani
- Center for Quantum Phenomena, Department of Physics, New York University, New York, NY, 10003, USA
| | - Igor Žutić
- Department of Physics, University at Buffalo, State University of New York, Buffalo, NY, 14260, USA.
| |
Collapse
|
30
|
Dardzinski D, Yu M, Moayedpour S, Marom N. Best practices for first-principles simulations of epitaxial inorganic interfaces. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:233002. [PMID: 35193122 DOI: 10.1088/1361-648x/ac577b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
At an interface between two materials physical properties and functionalities may be achieved, which would not exist in either material alone. Epitaxial inorganic interfaces are at the heart of semiconductor, spintronic, and quantum devices. First principles simulations based on density functional theory (DFT) can help elucidate the electronic and magnetic properties of interfaces and relate them to the structure and composition at the atomistic scale. Furthermore, DFT simulations can predict the structure and properties of candidate interfaces and guide experimental efforts in promising directions. However, DFT simulations of interfaces can be technically elaborate and computationally expensive. To help researchers embarking on such simulations, this review covers best practices for first principles simulations of epitaxial inorganic interfaces, including DFT methods, interface model construction, interface structure prediction, and analysis and visualization tools.
Collapse
Affiliation(s)
- Derek Dardzinski
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
| | - Maituo Yu
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
| | - Saeed Moayedpour
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
| | - Noa Marom
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
- Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
| |
Collapse
|
31
|
Choi SJ, Trauzettel B. Microscopic Theory of the Current-Voltage Characteristics of Josephson Tunnel Junctions. PHYSICAL REVIEW LETTERS 2022; 128:126801. [PMID: 35394303 DOI: 10.1103/physrevlett.128.126801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 12/20/2021] [Accepted: 03/07/2022] [Indexed: 06/14/2023]
Abstract
Deep theoretical understanding of the electrical response of Josephson junctions is indispensable regarding both recent discoveries of new kinds of superconductivity and technological advances such as superconducting quantum computers. Here, we study the microscopic theory of the dc current-biased I-V characteristics of Josephson tunnel junctions. We derive an analytical formula of the I-V characteristics of generic junctions. We identify subharmonics of the I-V characteristics and their underlying mechanism as the feedback effect of intrinsic ac currents generated by voltage pulses in the past. We apply our theory to analytically solve the Werthamer equation and describe various dc current-biased I-V characteristics as a function of softening of the superconducting gap. Strikingly, we identify voltage staircases of the I-V characteristics in a genuine Josephson junction without ac current bias or qubit dynamics. Our general analytical formalism opens new avenues for a microscopic understanding of I-V characteristics of Josephson junctions that have been limited to phenomenological models so far.
Collapse
Affiliation(s)
- Sang-Jun Choi
- Institute for Theoretical Physics and Astrophysics, University of Würzburg, D-97074 Würzburg, Germany
| | - Björn Trauzettel
- Institute for Theoretical Physics and Astrophysics, University of Würzburg, D-97074 Würzburg, Germany
- Würzburg-Dresden Cluster of Excellence ct.qmat, Germany
| |
Collapse
|
32
|
Kotetes P. Diagnosing topological phase transitions in 1D superconductors using Berry singularity markers. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:174003. [PMID: 35081520 DOI: 10.1088/1361-648x/ac4f1e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 01/26/2022] [Indexed: 06/14/2023]
Abstract
In this work I demonstrate how to characterize topological phase transitions in BDI symmetry class superconductors (SCs) in 1D, using the recently introduced approach of Berry singularity markers (BSMs). In particular, I apply the BSM method to the celebrated Kitaev chain model, as well as to a variant of it, which contains both nearest and next nearest neighbor equal spin pairings. Depending on the situation, I identify pairs of external fields which can detect the topological charges of the Berry singularities which are responsible for the various topological phase transitions. These pairs of fields consist of either a flux knob which controls the supercurrent flow through the SC, or, strain, combined with a field which can tune the chemical potential of the system. Employing the present BSM approach appears to be within experimental reach for topological nanowire hybrids.
Collapse
Affiliation(s)
- Panagiotis Kotetes
- CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| |
Collapse
|
33
|
Liu D, Zhang G, Cao Z, Zhang H, Liu DE. Universal Conductance Scaling of Andreev Reflections Using a Dissipative Probe. PHYSICAL REVIEW LETTERS 2022; 128:076802. [PMID: 35244417 DOI: 10.1103/physrevlett.128.076802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 01/25/2022] [Indexed: 06/14/2023]
Abstract
The Majorana search is caught up in an extensive debate about the false-positive signals from nontopological Andreev bound states. We introduce a remedy using the dissipative probe to generate electron-boson interaction. We theoretically show that the interaction-induced renormalization leads to significantly distinct universal zero-bias conductance behaviors, i.e., distinct characteristic power law in temperature, for different types of Andreev reflections, that show a sharp contrast to that of a Majorana zero mode. Various specific cases have been studied, including the cases in which two charges involved in an Andreev reflection process maintain or lose coherence, and the cases for multiple Andreev bound states with or without a Majorana. A transparent list of conductance features in each case is provided to help distinguish the observed subgap states in experiments, which also promotes the identification of Majorana zero modes.
Collapse
Affiliation(s)
- Donghao Liu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
| | - Gu Zhang
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Zhan Cao
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Hao Zhang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100184, China
| | - Dong E Liu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100184, China
| |
Collapse
|
34
|
Alfieri A, Anantharaman SB, Zhang H, Jariwala D. Nanomaterials for Quantum Information Science and Engineering. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022:e2109621. [PMID: 35139247 DOI: 10.1002/adma.202109621] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/04/2022] [Indexed: 06/14/2023]
Abstract
Quantum information science and engineering (QISE)-which entails the use of quantum mechanical states for information processing, communications, and sensing-and the area of nanoscience and nanotechnology have dominated condensed matter physics and materials science research in the 21st century. Solid-state devices for QISE have, to this point, predominantly been designed with bulk materials as their constituents. This review considers how nanomaterials (i.e., materials with intrinsic quantum confinement) may offer inherent advantages over conventional materials for QISE. The materials challenges for specific types of qubits, along with how emerging nanomaterials may overcome these challenges, are identified. Challenges for and progress toward nanomaterials-based quantum devices are condidered. The overall aim of the review is to help close the gap between the nanotechnology and quantum information communities and inspire research that will lead to next-generation quantum devices for scalable and practical quantum applications.
Collapse
Affiliation(s)
- Adam Alfieri
- Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Surendra B Anantharaman
- Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Huiqin Zhang
- Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Deep Jariwala
- Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA, 19104, USA
| |
Collapse
|
35
|
Zhang Y, Zhao WM, Zhang C, Wang P, Wang T, Li SC, Xing Z, Xing D. Anomalous Superconducting Proximity Effect in Bi 2 Se 3 /FeSe 0.5 Te 0.5 Thin-Film Heterojunctions. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2107799. [PMID: 34818689 DOI: 10.1002/adma.202107799] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/19/2021] [Indexed: 06/13/2023]
Abstract
The superconducting proximity effect (SPE) induces a superconductivity transition in otherwise non-superconducting thin films in proximity with a superconductor. The SPE usually occurs in real space and decays exponentially with film thickness. Herein, an abnormal SPE in a topological insulator (TI)/superconductor heterostructure is unveiled, which is attributed to the topologically protected surface state. Surprisingly, such abnormal SPE occurs in momentum space regardless of the TI film thickness, as long as the topological surface states are robust and form a continuous conduction loop. Combining transport measurements and scanning tunneling microscopy/spectroscopy techniques, the SPE in Bi2 Se3 /FeSe0.5 Te0.5 heterostructures is explored, where Bi2 Se3 is an ideal 3D topological insulator and FeSe0.5 Te0.5 a typical iron-based superconductor. As the thickness of the Bi2 Se3 thin film exceeds 400 nm, there still exists SPE-induced superconductivity on the surface of Bi2 Se3 thin film with a transition temperature Tc not less than 10 K. Such an extraordinary behavior is induced by the unique properties of topologically protected surface states of Bi2 Se3 . This research deepens the understanding of the important role of topologically protected surface states in the SPE.
Collapse
Affiliation(s)
- Yalin Zhang
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Wei-Min Zhao
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- School of Physics, Nanjing University, Nanjing, 210093, China
| | - Chunchen Zhang
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Peng Wang
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, China
| | - Tong Wang
- Department of Mathematics, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China
| | - Shao-Chun Li
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- School of Physics, Nanjing University, Nanjing, 210093, China
| | - Zhongwen Xing
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- School of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China
| | - Dingyu Xing
- National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
- School of Physics, Nanjing University, Nanjing, 210093, China
| |
Collapse
|
36
|
Marra P, Nigro A. Majorana/Andreev crossover and the fate of the topological phase transition in inhomogeneous nanowires. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:124001. [PMID: 34929683 DOI: 10.1088/1361-648x/ac44d2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
Majorana bound states (MBS) and Andreev bound states (ABS) in realistic Majorana nanowires setups have similar experimental signatures which make them hard to distinguishing one from the other. Here, we characterize the continuous Majorana/Andreev crossover interpolating between fully-separated, partially-separated, and fully-overlapping Majorana modes, in terms of global and local topological invariants, fermion parity, quasiparticle densities, Majorana pseudospin and spin polarizations, density overlaps and transition probabilities between opposite Majorana components. We found that in inhomogeneous wires, the transition between fully-overlapping trivial ABS and nontrivial MBS does not necessarily mandate the closing of the bulk gap of quasiparticle excitations, but a simple parity crossing of partially-separated Majorana modes (ps-MM) from trivial to nontrivial regimes. We demonstrate that fully-separated and fully-overlapping Majorana modes correspond to the two limiting cases at the opposite sides of a continuous crossover: the only distinction between the two can be obtained by estimating the degree of separations of the Majorana components. This result does not contradict the bulk-edge correspondence: indeed, the field inhomogeneities driving the Majorana/Andreev crossover have a length scale comparable with the nanowire length, and therefore correspond to a nonlocal perturbation which breaks the topological protection of the MBS.
Collapse
Affiliation(s)
- Pasquale Marra
- Graduate School of Mathematical Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo 153-8914, Japan
- Department of Physics, and Research and Education Center for Natural Sciences, Keio University, 4-1-1 Hiyoshi, Yokohama, Kanagawa 223-8521, Japan
| | - Angela Nigro
- Dipartimento di Fisica 'E. R. Caianiello', Università degli Studi di Salerno, 84084 Fisciano (Salerno), Italy
- Consiglio Nazionale delle Ricerche CNR-SPIN, UOS Salerno, 84084 Fisciano (Salerno), Italy
| |
Collapse
|
37
|
Song MS, Koren T, Załuska-Kotur M, Buczko R, Avraham N, Kacman P, Shtrikman H, Beidenkopf H. Sub-Band Spectrum Engineering via Structural Order in Tapered Nanowires. NANO LETTERS 2021; 21:10215-10221. [PMID: 34882412 PMCID: PMC8704197 DOI: 10.1021/acs.nanolett.1c03071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 11/30/2021] [Indexed: 06/13/2023]
Abstract
The cross-sectional dimensions of nanowires set the quantization conditions for the electronic subbands they host. These can be used as a platform to realize one-dimesional topological superconductivity. Here we develop a protocol that forces such nanowires to kink and change their growth direction. Consequently, a thin rectangular nanoplate is formed, which gradually converges into a very thin square tip. We characterize the resulting tapered nanowires structurally and spectroscopically by scanning and transmission electron microscopy and scanning tunneling microscopy and spectroscopy and model their growth. A unique structure composed of ordered rows of atoms on the (110) facet of the nanoflag is further revealed by atomically resolved topography and modeled by simulations. We discuss possible advantages tapered InAs nanowires offer for Majorana zero-mode realization and manipulation.
Collapse
Affiliation(s)
- Man Suk Song
- Department
of Condensed Matter Physics, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Tom Koren
- Department
of Condensed Matter Physics, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Magdalena Załuska-Kotur
- Institute
of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, Warsaw PL-02-668, Poland
| | - Ryszard Buczko
- Institute
of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, Warsaw PL-02-668, Poland
| | - Nurit Avraham
- Department
of Condensed Matter Physics, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Perla Kacman
- Institute
of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, Warsaw PL-02-668, Poland
| | - Hadas Shtrikman
- Department
of Condensed Matter Physics, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Haim Beidenkopf
- Department
of Condensed Matter Physics, Weizmann Institute
of Science, Rehovot 7610001, Israel
| |
Collapse
|
38
|
Nanoresonator Enhancement of Majorana-Fermion-Induced Slow Light in Superconducting Iron Chains. MICROMACHINES 2021; 12:mi12121435. [PMID: 34945284 PMCID: PMC8705128 DOI: 10.3390/mi12121435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 11/21/2021] [Accepted: 11/21/2021] [Indexed: 11/17/2022]
Abstract
We theoretically investigate Fano resonance in the absorption spectrum of a quantum dot (QD) based on a hybrid QD-nanomechanical resonator (QD-NR) system mediated by Majorana fermions (MFs) in superconducting iron (Fe) chains. The absorption spectra exhibit a series of asymmetric Fano line shapes, which are accompanied by the rapid normal phase dispersion and induce the optical propagation properties such as the slow light effect under suitable parametric regimes. The results indicated that the slow light induced by MFs can be obtained under different coupling regimes and different detuning regimes. Moreover, we also investigated the role of the NR, and the NR behaving as a phonon cavity enhances the slow light effect.
Collapse
|
39
|
Bäuml C, Bauriedl L, Marganska M, Grifoni M, Strunk C, Paradiso N. Supercurrent and Phase Slips in a Ballistic Carbon Nanotube Bundle Embedded into a van der Waals Heterostructure. NANO LETTERS 2021; 21:8627-8633. [PMID: 34634912 DOI: 10.1021/acs.nanolett.1c02565] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We demonstrate long-range superconducting correlations in a several-micrometers-long carbon nanotube bundle encapsulated in a van der Waals stack between hBN and NbSe2. We show that a substantial supercurrent flows through the nanotube section beneath the NbSe2 crystal as well as through the 2 μm long section not in contact with it. The large in-plane critical magnetic field of this supercurrent is an indication that even inside the carbon nanotube Cooper pairs enjoy a degree of paramagnetic protection typical of the parent Ising superconductor. As expected for superconductors of nanoscopic cross section, the current-induced breakdown of superconductivity is characterized by resistance steps due to the nucleation of phase slip centers. All elements of our hybrid device are active building blocks of several recently proposed setups for realization of Majorana fermions in carbon nanotubes.
Collapse
Affiliation(s)
- Christian Bäuml
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, 93040 Regensburg, Germany
| | - Lorenz Bauriedl
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, 93040 Regensburg, Germany
| | - Magdalena Marganska
- Institut für Theoretische Physik, University of Regensburg, 93040 Regensburg, Germany
| | - Milena Grifoni
- Institut für Theoretische Physik, University of Regensburg, 93040 Regensburg, Germany
| | - Christoph Strunk
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, 93040 Regensburg, Germany
| | - Nicola Paradiso
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, 93040 Regensburg, Germany
| |
Collapse
|
40
|
Hassan SA, Wu BH, Xu XF, Wang CR, Cao JC. Bending effect on the Majorana bound states in planar Josephson junctions. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:385001. [PMID: 34171850 DOI: 10.1088/1361-648x/ac0ea7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
We consider the bending effect on the formation of Majorana bound states (MBSs) in planar Josephson junctions where the normal stripe is tilted in a V shape. Our results show that the MBSs remain robust for moderate bending angles. Beyond some critical angles, the degradation of MBSs can be revealed by its eigenspectrum as well as the Majorana polarization (MP). Our results show that the parameter space of bending angle for robust MBSs can be significantly enlarged by tuning the superconducting phase difference across the Josephson junction. These findings suggest that the interplay of the junction geometry and the device parameters provides richer degree of freedom in designing topological superconducting devices for future applications. The MP analysis is an indispensable tool for characterizing the Majorana states.
Collapse
Affiliation(s)
- S A Hassan
- Department of Applied Physics, Donghua University, 2999 North Renmin Road, Shanghai, 201620, People's Republic of China
| | - B H Wu
- Department of Applied Physics, Donghua University, 2999 North Renmin Road, Shanghai, 201620, People's Republic of China
| | - X F Xu
- Department of Applied Physics, Donghua University, 2999 North Renmin Road, Shanghai, 201620, People's Republic of China
| | - C R Wang
- Department of Applied Physics, Donghua University, 2999 North Renmin Road, Shanghai, 201620, People's Republic of China
| | - J C Cao
- Key Laboratory of Terahertz Solid-State Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, People's Republic of China
| |
Collapse
|
41
|
Wang Z, Cheng S, Liu X, Jiang H. Topological kink states in graphene. NANOTECHNOLOGY 2021; 32:402001. [PMID: 34161935 DOI: 10.1088/1361-6528/ac0dd8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 06/23/2021] [Indexed: 06/13/2023]
Abstract
Due to the unique band structure, graphene exhibits a number of exotic electronic properties that have not been observed in other materials. Among them, it has been demonstrated that there exist the one-dimensional valley-polarized topological kink states localized in the vicinity of the domain wall of graphene systems, where a bulk energy gap opens due to the inversion symmetry breaking. Notably, the valley-momentum locking nature makes the topological kink states attractive to the property manipulation in valleytronics. This paper systematically reviews both the theoretical research and experimental progress on topological kink states in monolayer graphene, bilayer graphene and graphene-like classical wave systems. Besides, various applications of topological kink states, including the valley filter, current partition, current manipulation, Majorana zero modes and etc, are also introduced.
Collapse
Affiliation(s)
- Zibo Wang
- College of Physics and Electronic Engineering, Sichuan Normal University, Chengdu 610068, People's Republic of China
- Center for Computational Sciences, Sichuan Normal University, Chengdu 610068, People's Republic of China
| | - Shuguang Cheng
- Department of Physics, Northwest University, Xi'an 710069, People's Republic of China
| | - Xiao Liu
- School of Physical Science and Technology, Soochow University, Suzhou 215006, People's Republic of China
| | - Hua Jiang
- School of Physical Science and Technology, Soochow University, Suzhou 215006, People's Republic of China
- Institute for Advanced Study of Soochow University, Suzhou 215006, People's Republic of China
| |
Collapse
|
42
|
Kanne T, Marnauza M, Olsteins D, Carrad DJ, Sestoft JE, de Bruijckere J, Zeng L, Johnson E, Olsson E, Grove-Rasmussen K, Nygård J. Epitaxial Pb on InAs nanowires for quantum devices. NATURE NANOTECHNOLOGY 2021; 16:776-781. [PMID: 33972757 DOI: 10.1038/s41565-021-00900-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 03/11/2021] [Indexed: 05/21/2023]
Abstract
Semiconductor-superconductor hybrids are widely used to realize complex quantum phenomena, such as topological superconductivity and spins coupled to Cooper pairs. Accessing new, exotic regimes at high magnetic fields and increasing operating temperatures beyond the state-of-the-art requires new, epitaxially matched semiconductor-superconductor materials. One challenge is the generation of favourable conditions for heterostructural formation between materials with the desired properties. Here we harness an increased knowledge of metal-on-semiconductor growth to develop InAs nanowires with epitaxially matched, single-crystal, atomically flat Pb films with no axial grain boundaries. These highly ordered heterostructures have a critical temperature of 7 K and a superconducting gap of 1.25 meV, which remains hard at 8.5 T, and therefore they offer a parameter space more than twice as large as those of alternative semiconductor-superconductor hybrids. Additionally, InAs/Pb island devices exhibit magnetic field-driven transitions from a Cooper pair to single-electron charging, a prerequisite for use in topological quantum computation. Semiconductor-Pb hybrids potentially enable access to entirely new regimes for a number of different quantum systems.
Collapse
Affiliation(s)
- Thomas Kanne
- Center for Quantum Devices & Nano-Science Center, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
| | - Mikelis Marnauza
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Dags Olsteins
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Damon J Carrad
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Joachim E Sestoft
- Center for Quantum Devices & Nano-Science Center, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Joeri de Bruijckere
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
- Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands
| | - Lunjie Zeng
- Department of Physics, Chalmers University of Technology, Gothenburg, Sweden
| | - Erik Johnson
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Eva Olsson
- Department of Physics, Chalmers University of Technology, Gothenburg, Sweden
| | - Kasper Grove-Rasmussen
- Center for Quantum Devices & Nano-Science Center, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Jesper Nygård
- Center for Quantum Devices & Nano-Science Center, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
| |
Collapse
|
43
|
Verma I, Salimian S, Zannier V, Heun S, Rossi F, Ercolani D, Beltram F, Sorba L. High-Mobility Free-Standing InSb Nanoflags Grown on InP Nanowire Stems for Quantum Devices. ACS APPLIED NANO MATERIALS 2021; 4:5825-5833. [PMID: 34308268 PMCID: PMC8291043 DOI: 10.1021/acsanm.1c00734] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/07/2021] [Indexed: 05/31/2023]
Abstract
High-quality heteroepitaxial two-dimensional (2D) InSb layers are very difficult to realize because of the large lattice mismatch with other widespread semiconductor substrates. A way around this problem is to grow free-standing 2D InSb nanostructures on nanowire (NW) stems, thanks to the capability of NWs to efficiently relax elastic strain along the sidewalls when lattice-mismatched semiconductor systems are integrated. In this work, we optimize the morphology of free-standing 2D InSb nanoflags (NFs). In particular, robust NW stems, optimized growth parameters, and the use of reflection high-energy electron diffraction (RHEED) to precisely orient the substrate for preferential growth are implemented to increase the lateral size of the 2D InSb NFs. Transmission electron microscopy (TEM) analysis of these NFs reveals defect-free zinc blend crystal structure, stoichiometric composition, and relaxed lattice parameters. The resulting NFs are large enough to fabricate Hall-bar contacts with suitable length-to-width ratio enabling precise electrical characterization. An electron mobility of ∼29 500 cm2/(V s) is measured, which is the highest value reported for free-standing 2D InSb nanostructures in literature. We envision the use of 2D InSb NFs for fabrication of advanced quantum devices.
Collapse
Affiliation(s)
- Isha Verma
- NEST,
Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza San Silvestro 12, I-56127 Pisa, Italy
| | - Sedighe Salimian
- NEST,
Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza San Silvestro 12, I-56127 Pisa, Italy
| | - Valentina Zannier
- NEST,
Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza San Silvestro 12, I-56127 Pisa, Italy
| | - Stefan Heun
- NEST,
Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza San Silvestro 12, I-56127 Pisa, Italy
| | - Francesca Rossi
- IMEM-CNR, Parco Area delle Scienze 37/A, I-43124 Parma, Italy
| | - Daniele Ercolani
- NEST,
Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza San Silvestro 12, I-56127 Pisa, Italy
| | - Fabio Beltram
- NEST,
Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza San Silvestro 12, I-56127 Pisa, Italy
| | - Lucia Sorba
- NEST,
Istituto Nanoscienze-CNR and Scuola Normale Superiore, Piazza San Silvestro 12, I-56127 Pisa, Italy
| |
Collapse
|
44
|
Pendharkar M, Zhang B, Wu H, Zarassi A, Zhang P, Dempsey CP, Lee JS, Harrington SD, Badawy G, Gazibegovic S, Op Het Veld RLM, Rossi M, Jung J, Chen AH, Verheijen MA, Hocevar M, Bakkers EPAM, Palmstrøm CJ, Frolov SM. Parity-preserving and magnetic field-resilient superconductivity in InSb nanowires with Sn shells. Science 2021; 372:508-511. [PMID: 33858990 DOI: 10.1126/science.aba5211] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/13/2021] [Indexed: 11/02/2022]
Abstract
Improving materials used to make qubits is crucial to further progress in quantum information processing. Of particular interest are semiconductor-superconductor heterostructures that are expected to form the basis of topological quantum computing. We grew semiconductor indium antimonide nanowires that were coated with shells of tin of uniform thickness. No interdiffusion was observed at the interface between Sn and InSb. Tunnel junctions were prepared by in situ shadowing. Despite the lack of lattice matching between Sn and InSb, a 15-nanometer-thick shell of tin was found to induce a hard superconducting gap, with superconductivity persisting in magnetic field up to 4 teslas. A small island of Sn-InSb exhibits the two-electron charging effect. These findings suggest a less restrictive approach to fabricating superconducting and topological quantum circuits.
Collapse
Affiliation(s)
- M Pendharkar
- Electrical and Computer Engineering, University of California, Santa Barbara, CA 93106, USA
| | - B Zhang
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - H Wu
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - A Zarassi
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - P Zhang
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - C P Dempsey
- Electrical and Computer Engineering, University of California, Santa Barbara, CA 93106, USA
| | - J S Lee
- California NanoSystems Institute, University of California, Santa Barbara, CA 93106, USA
| | - S D Harrington
- Materials Department, University of California, Santa Barbara, CA 93106, USA
| | - G Badawy
- Eindhoven University of Technology, 5600 MB Eindhoven, Netherlands
| | - S Gazibegovic
- Eindhoven University of Technology, 5600 MB Eindhoven, Netherlands
| | | | - M Rossi
- Eindhoven University of Technology, 5600 MB Eindhoven, Netherlands
| | - J Jung
- Eindhoven University of Technology, 5600 MB Eindhoven, Netherlands
| | - A-H Chen
- Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 38000 Grenoble, France
| | - M A Verheijen
- Eindhoven University of Technology, 5600 MB Eindhoven, Netherlands
| | - M Hocevar
- Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 38000 Grenoble, France
| | - E P A M Bakkers
- Eindhoven University of Technology, 5600 MB Eindhoven, Netherlands
| | - C J Palmstrøm
- Electrical and Computer Engineering, University of California, Santa Barbara, CA 93106, USA.,California NanoSystems Institute, University of California, Santa Barbara, CA 93106, USA.,Materials Department, University of California, Santa Barbara, CA 93106, USA
| | - S M Frolov
- Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA.
| |
Collapse
|
45
|
Kornich V, Huang X, Repin E, Nazarov YV. Braiding and All Quantum Operations with Majorana Modes in 1D. PHYSICAL REVIEW LETTERS 2021; 126:117701. [PMID: 33798362 DOI: 10.1103/physrevlett.126.117701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 02/12/2021] [Indexed: 06/12/2023]
Abstract
We propose a scheme to perform braiding and all other unitary operations with Majorana modes in one dimension that, in contrast to previous proposals, is solely based on resonant manipulation involving the first excited state extended over the modes. The detection of the population of the excited state also enables initialization and read-out. We provide an elaborated illustration of the scheme with a concrete device.
Collapse
Affiliation(s)
- Viktoriia Kornich
- Kavli Institute of Nanoscience, Delft University of Technology, 2628 CJ Delft, Netherlands
| | - Xiaoli Huang
- Kavli Institute of Nanoscience, Delft University of Technology, 2628 CJ Delft, Netherlands
| | - Evgeny Repin
- Kavli Institute of Nanoscience, Delft University of Technology, 2628 CJ Delft, Netherlands
| | - Yuli V Nazarov
- Kavli Institute of Nanoscience, Delft University of Technology, 2628 CJ Delft, Netherlands
| |
Collapse
|
46
|
Perla P, Fonseka HA, Zellekens P, Deacon R, Han Y, Kölzer J, Mörstedt T, Bennemann B, Espiari A, Ishibashi K, Grützmacher D, Sanchez AM, Lepsa MI, Schäpers T. Fully in situ Nb/InAs-nanowire Josephson junctions by selective-area growth and shadow evaporation. NANOSCALE ADVANCES 2021; 3:1413-1421. [PMID: 36132855 PMCID: PMC9418346 DOI: 10.1039/d0na00999g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 01/17/2021] [Indexed: 06/14/2023]
Abstract
Josephson junctions based on InAs semiconducting nanowires and Nb superconducting electrodes are fabricated in situ by a special shadow evaporation scheme for the superconductor electrode. Compared to other metallic superconductors such as Al, Nb has the advantage of a larger superconducting gap which allows operation at higher temperatures and magnetic fields. Our junctions are fabricated by shadow evaporation of Nb on pairs of InAs nanowires grown selectively on two adjacent tilted Si (111) facets and crossing each other at a small distance. The upper wire relative to the deposition source acts as a shadow mask determining the gap of the superconducting electrodes on the lower nanowire. Electron microscopy measurements show that the fully in situ fabrication method gives a clean InAs/Nb interface. A clear Josephson supercurrent is observed in the current-voltage characteristics, which can be controlled by a bottom gate. The large excess current indicates a high junction transparency. Under microwave radiation, pronounced integer Shapiro steps are observed suggesting a sinusoidal current-phase relation. Owing to the large critical field of Nb, the Josephson supercurrent can be maintained to magnetic fields exceeding 1 T. Our results show that in situ prepared Nb/InAs nanowire contacts are very interesting candidates for superconducting quantum circuits requiring large magnetic fields.
Collapse
Affiliation(s)
- Pujitha Perla
- Peter Grünberg Institut (PGI-9), Forschungszentrum Jülich 52425 Jülich Germany +49 2461 61 2940 +49 2461 61 2668
- JARA-Fundamentals of Future Information Technology, Jülich-Aachen Research Alliance, Forschungszentrum Jülich, RWTH Aachen University Germany
| | - H Aruni Fonseka
- Department of Physics, University of Warwick Coventry CV4 7AL UK
| | - Patrick Zellekens
- Peter Grünberg Institut (PGI-9), Forschungszentrum Jülich 52425 Jülich Germany +49 2461 61 2940 +49 2461 61 2668
- JARA-Fundamentals of Future Information Technology, Jülich-Aachen Research Alliance, Forschungszentrum Jülich, RWTH Aachen University Germany
| | - Russell Deacon
- RIKEN Center for Emergent Matter Science and Advanced Device Laboratory 351-0198 Saitama Japan
| | - Yisong Han
- Department of Physics, University of Warwick Coventry CV4 7AL UK
| | - Jonas Kölzer
- Peter Grünberg Institut (PGI-9), Forschungszentrum Jülich 52425 Jülich Germany +49 2461 61 2940 +49 2461 61 2668
- JARA-Fundamentals of Future Information Technology, Jülich-Aachen Research Alliance, Forschungszentrum Jülich, RWTH Aachen University Germany
| | - Timm Mörstedt
- Peter Grünberg Institut (PGI-9), Forschungszentrum Jülich 52425 Jülich Germany +49 2461 61 2940 +49 2461 61 2668
- JARA-Fundamentals of Future Information Technology, Jülich-Aachen Research Alliance, Forschungszentrum Jülich, RWTH Aachen University Germany
| | - Benjamin Bennemann
- Peter Grünberg Institut (PGI-9), Forschungszentrum Jülich 52425 Jülich Germany +49 2461 61 2940 +49 2461 61 2668
- JARA-Fundamentals of Future Information Technology, Jülich-Aachen Research Alliance, Forschungszentrum Jülich, RWTH Aachen University Germany
| | - Abbas Espiari
- Peter Grünberg Institut (PGI-9), Forschungszentrum Jülich 52425 Jülich Germany +49 2461 61 2940 +49 2461 61 2668
- JARA-Fundamentals of Future Information Technology, Jülich-Aachen Research Alliance, Forschungszentrum Jülich, RWTH Aachen University Germany
| | - Koji Ishibashi
- RIKEN Center for Emergent Matter Science and Advanced Device Laboratory 351-0198 Saitama Japan
| | - Detlev Grützmacher
- Peter Grünberg Institut (PGI-9), Forschungszentrum Jülich 52425 Jülich Germany +49 2461 61 2940 +49 2461 61 2668
- JARA-Fundamentals of Future Information Technology, Jülich-Aachen Research Alliance, Forschungszentrum Jülich, RWTH Aachen University Germany
- Peter Grünberg Institut (PGI-10), Forschungszentrum Jülich 52425 Jülich Germany
| | - Ana M Sanchez
- Department of Physics, University of Warwick Coventry CV4 7AL UK
| | - Mihail Ion Lepsa
- JARA-Fundamentals of Future Information Technology, Jülich-Aachen Research Alliance, Forschungszentrum Jülich, RWTH Aachen University Germany
- Peter Grünberg Institut (PGI-10), Forschungszentrum Jülich 52425 Jülich Germany
| | - Thomas Schäpers
- Peter Grünberg Institut (PGI-9), Forschungszentrum Jülich 52425 Jülich Germany +49 2461 61 2940 +49 2461 61 2668
- JARA-Fundamentals of Future Information Technology, Jülich-Aachen Research Alliance, Forschungszentrum Jülich, RWTH Aachen University Germany
| |
Collapse
|
47
|
Yang Z, Yang Q, Hu J, Liu DE. Dissipative Floquet Majorana Modes in Proximity-Induced Topological Superconductors. PHYSICAL REVIEW LETTERS 2021; 126:086801. [PMID: 33709754 DOI: 10.1103/physrevlett.126.086801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 08/27/2020] [Accepted: 01/28/2021] [Indexed: 06/12/2023]
Abstract
We study a realistic Floquet topological superconductor, a periodically driven nanowire proximitized to an equilibrium s-wave superconductor. Because of the strong energy and density fluctuations caused by the superconducting proximity effect, the Floquet Majorana wire becomes dissipative. We show that the Floquet band structure is still preserved in this dissipative system. In particular, we find that the Floquet Majorana zero and π modes can no longer be simply described by the Floquet topological band theory. We also propose an effective model to simplify the calculation of the lifetime of these Floquet Majoranas and find that the lifetime can be engineered by the external driving field.
Collapse
Affiliation(s)
- Zhesen Yang
- Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Qinghong Yang
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
| | - Jiangping Hu
- Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Kavli Institute for Theoretical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
- South Bay Interdisciplinary Science Center, Dongguan, Guangdong 523808, China
| | - Dong E Liu
- State Key Laboratory of Low Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084, China
- Beijing Academy of Quantum Information Sciences, Beijing 100193, China
- Frontier Science Center for Quantum Information, Beijing 100184, China
| |
Collapse
|
48
|
Udupa A, Banerjee A, Sengupta K, Sen D. One-dimensional spin-orbit coupled Dirac system with extended s-wave superconductivity: Majorana modes and Josephson effects. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:145301. [PMID: 33470985 DOI: 10.1088/1361-648x/abdd63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
Motivated by the spin-momentum locking of electrons at the boundaries of certain topological insulators, we study a one-dimensional system of spin-orbit coupled massless Dirac electrons withs-wave superconducting pairing. As a result of the spin-orbit coupling, our model has only two kinds of linearly dispersing modes, and we take these to be right-moving spin-up and left-moving spin-down. Both lattice and continuum models are studied. In the lattice model, we find that a single Majorana zero energy mode appears at each end of a finite system provided that thes-wave pairing has an extended form, with the nearest-neighbor pairing being larger than the on-site pairing. We confirm this both numerically and analytically by calculating the winding number. We find that the continuum model also has zero energy end modes. Next we study a lattice version of a model with both Schrödinger and Dirac-like terms and find that the model hosts a topological transition between topologically trivial and non-trivial phases depending on the relative strength of the Schrödinger and Dirac terms. We then study a continuum system consisting of twos-wave superconductors with different phases of the pairing, with aδ-function potential barrier lying at the junction of the two superconductors. Remarkably, we find that the system has asingleAndreev bound state (ABS) which is localized at the junction. When the pairing phase difference crosses a multiple of 2π, an ABS touches the top of the superconducting gap and disappears, and a different state appears from the bottom of the gap. We also study the AC Josephson effect in such a junction with a voltage bias that has both a constantV0and a term which oscillates with a frequencyω. We find that, in contrast to standard Josephson junctions, Shapiro plateaus appear when the Josephson frequencyωJ= 2eV0/ℏis a rational fraction ofω. We discuss experiments which can realize such junctions.
Collapse
Affiliation(s)
- Adithi Udupa
- Center for High Energy Physics, Indian Institute of Science, Bengaluru 560012, India
| | - Abhishek Banerjee
- Center for High Energy Physics, Indian Institute of Science, Bengaluru 560012, India
- Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - K Sengupta
- School of Physical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
| | - Diptiman Sen
- Center for High Energy Physics, Indian Institute of Science, Bengaluru 560012, India
- Department of Physics, Indian Institute of Science, Bengaluru 560012, India
| |
Collapse
|
49
|
Samarawickrama P, Dulal R, Fu Z, Erugu U, Wang W, Ackerman J, Leonard B, Tang J, Chien T, Tian J. Two-Dimensional 2M-WS 2 Nanolayers for Superconductivity. ACS OMEGA 2021; 6:2966-2972. [PMID: 33553915 PMCID: PMC7860099 DOI: 10.1021/acsomega.0c05327] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 01/08/2021] [Indexed: 06/12/2023]
Abstract
Recently, a newly discovered VIB group transition metal dichalcogenide (TMD) material, 2M-WS2, has attracted extensive attention due to its interesting physical properties such as topological superconductivity, nodeless superconductivity, and anisotropic Majorana bound states. However, the techniques to grow high-quality 2M-WS2 bulk crystals and the study of their physical properties at the nanometer scale are still limited. In this work, we report a new route to grow high-quality 2M-WS2 single crystals and the observation of superconductivity in its thin layers. The crystal structure of the as-grown 2M-WS2 crystals was determined by X-ray diffraction (XRD) and scanning tunneling microscopy (STM). The chemical composition of the 2M-WS2 crystals was determined by energy dispersive X-ray spectroscopy (EDS) analysis. At 77 K, we observed the spatial variation of the local tunneling conductance (dI/dV) of the 2M-WS2 thin flakes by scanning tunneling spectroscopy (STS). Our low temperature transport measurements demonstrate clear signatures of superconductivity of a 25 nm-thick 2M-WS2 flake with a critical temperature (T C) of ∼8.5 K and an upper critical field of ∼2.5 T at T = 1.5 K. Our work may pave new opportunities in studying the topological superconductivity at the atomic scale in simple 2D TMD materials.
Collapse
Affiliation(s)
- Piumi Samarawickrama
- Department
of Physics & Astronomy, University of
Wyoming, Laramie, Wyoming 82071, United States
| | - Rabindra Dulal
- Department
of Physics & Astronomy, University of
Wyoming, Laramie, Wyoming 82071, United States
| | - Zhuangen Fu
- Department
of Physics & Astronomy, University of
Wyoming, Laramie, Wyoming 82071, United States
| | - Uppalaiah Erugu
- Department
of Physics & Astronomy, University of
Wyoming, Laramie, Wyoming 82071, United States
| | - Wenyong Wang
- Department
of Physics & Astronomy, University of
Wyoming, Laramie, Wyoming 82071, United States
| | - John Ackerman
- Department
of Chemical Engineering, University of Wyoming, Laramie, Wyoming 82071, United States
- Resonant
Sciences, Beavercreek, Ohio 45430, United
States
| | - Brian Leonard
- Department
of Chemistry, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Jinke Tang
- Department
of Physics & Astronomy, University of
Wyoming, Laramie, Wyoming 82071, United States
| | - TeYu Chien
- Department
of Physics & Astronomy, University of
Wyoming, Laramie, Wyoming 82071, United States
| | - Jifa Tian
- Department
of Physics & Astronomy, University of
Wyoming, Laramie, Wyoming 82071, United States
| |
Collapse
|
50
|
Investigation of electrodeposition kinetics of In, Sb, and Zn for advanced designing of InSb and ZnSb thin films. J Electroanal Chem (Lausanne) 2021. [DOI: 10.1016/j.jelechem.2020.114967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|