Emergent Josephson current of \(N=1\) chiral topological superconductor in quantum anomalous Hall insulator/superconductor heterostructures

• Published in: arXiv.org
• Main Authors: Chui-Zhen, Chen, He, James Jun, Dong-Hui, Xu, Law, K T
• Format: Paper
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 05.10.2018
• Subjects: Electron gas; Heterostructures; Josephson junctions; Parameter estimation; Resistance; Topological superconductors
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1810.02661

Recently, a quantum anomalous Hall insulator (QAHI)/superconductor heterostructure has been realized and shows half-quantized conductance plateaus in two-terminal conductance measurements [Q. L. He \textit{et al.}, Science {\bf357}, 294 (2017)]. The half-quantized conductance plateaus are considered as a solid evidence of chiral Majorana edge modes. However, there is a strong debate over the origin of the half-quantized conductance plateaus. In this work, we propose a Josephson junction based on the QAHI/superconductor heterostructure to identify the existence of chiral Majorana edge modes. We find that the critical Josephson current dramatically increases to a peak value when a half-quantized conductance plateau \(\sigma_{12}=e^2/2h\) is showing up for the \(N=1\) chiral topological superconductor phase with a single chiral Majorana mode. Furthermore, we show that the critical Josephson current of the \(N=1\) chiral topological superconductor exhibits an \(h/e\)-period oscillation and is robust to disorder, in contrast to the behaviors of conventional two-dimensional electron gas systems. We also estimate experimentally relevant parameters and believe that the supercurrent can be observed in experiments.