Title
Distinguishing trivial and topological zero-energy states in long nanowire junctions
Date Issued
01 July 2021
Access level
open access
Resource Type
journal article
Author(s)
Black-Schaffer A.M.
Uppsala University
Publisher(s)
American Physical Society
Abstract
The emergence of zero-energy states in nontopological superconductors represents an inevitable problem that obscures the proper identification of zero-energy Majorana bound states (MBSs) and prevents their use as topologically protected qubits. In this Research Letter we investigate long superconductor-normal-superconductor junctions where trivial zero-energy states, robust over a large range of parameters, appear as a result of helicity and confinement in the normal region. We demonstrate that both equilibrium supercurrents and critical currents are sensitive to variations in the length of the superconductor regions in the topological phase hosting MBSs but, remarkably, no such length dependence exists when robust, but trivial, zero-energy states are present. This strikingly different response originates from the nonlocal nature of the MBSs, and we therefore propose it as a simple protocol for distinguishing between trivial and topological zero-energy states.
Volume
104
Issue
2
Number
L020501
Language
English
OCDE Knowledge area
Física de la materia condensada
Scopus EID
2-s2.0-85109145135
Source
Physical Review B
ISSN of the container
24699950
Sponsor(s)
We thank J. C. Estrada Saldaña and E. Lee for insightful and motivating discussions. We acknowledge financial support from the Swedish Research Council (Vetenskapsrådet Grant No. 2018-03488), the Knut and Alice Wallenberg Foundation through the Wallenberg Academy Fellows program, and the EU-COST Action CA-16218 NANCOHYBRI.
Knut och Alice Wallenbergs Stiftelse
Sources of information:
Directorio de Producción Científica
Scopus