Superconducting Quantum Interference in Edge State Josephson Junctions

authored by: Tamás Haidekker Galambos, Silas Hoffman, Patrik Recher, Jelena Klinovaja, Daniel Loss
Abstract: We study superconducting quantum interference in a Josephson junction linked via edge states in two-dimensional (2D) insulators. We consider two scenarios in which the 2D insulator is either a topological or a trivial insulator supporting one-dimensional (1D) helical or nonhelical edge states, respectively. In equilibrium, we find that the qualitative dependence of critical supercurrent on the flux through the junction is insensitive to the helical nature of the mediating states and can, therefore, not be used to verify the topological features of the underlying insulator. However, upon applying a finite voltage bias smaller than the superconducting gap to a relatively long junction, the finite-frequency interference pattern in the nonequilibrium transport current is qualitatively different for helical edge states as compared to nonhelical ones.
External Organisation(s): University of Basel
University of Florida
Technische Universität Braunschweig
Type: Article
Journal: Physical review letters
Volume: 125
ISSN: 0031-9007
Publication date: 10.2020
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Physics and Astronomy(all)
Electronic version(s): https://doi.org/10.1103/PhysRevLett.125.157701 (Access: Unknown)

BibTeX

@article{80e77428922a4451adc53c4412a85265,
title = "Superconducting Quantum Interference in Edge State Josephson Junctions",
abstract = "We study superconducting quantum interference in a Josephson junction linked via edge states in two-dimensional (2D) insulators. We consider two scenarios in which the 2D insulator is either a topological or a trivial insulator supporting one-dimensional (1D) helical or nonhelical edge states, respectively. In equilibrium, we find that the qualitative dependence of critical supercurrent on the flux through the junction is insensitive to the helical nature of the mediating states and can, therefore, not be used to verify the topological features of the underlying insulator. However, upon applying a finite voltage bias smaller than the superconducting gap to a relatively long junction, the finite-frequency interference pattern in the nonequilibrium transport current is qualitatively different for helical edge states as compared to nonhelical ones.",
author = "{Haidekker Galambos}, Tam{\'a}s and Silas Hoffman and Patrik Recher and Jelena Klinovaja and Daniel Loss",
note = "Funding information: We are grateful for fruitful discussions with A. Geresdi, D. Miserev, C. Reeg, M. Thakurathi, F. Schulz, O. Dmytruk, V. Chua, and P. Aseev. T. H. G. acknowledges support from the “Quantum Computing and Quantum Technologies” Ph.D. School of the University of Basel. This work was supported by the Swiss National Science Foundation and NCCR QSIT. This project received funding from the European Unions Horizon 2020 research and innovation program (ERC Starting Grant, grant Agreement No. 757725). P. R. acknowledges funding from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany{\textquoteright}s Excellence Strategy—EXC-2123 QuantumFrontiers—390837967.",
year = "2020",
month = oct,
doi = "10.1103/PhysRevLett.125.157701",
language = "English",
volume = "125",
journal = "Physical review letters",
issn = "0031-9007",
publisher = "American Physical Society",
number = "15",
}