Quasi-one-dimensional Quantum Anomalous Hall Systems as New Platforms for Scalable Topological Quantum Computation

TL;DR

This paper demonstrates that quasi-one-dimensional quantum anomalous Hall systems can host localized Majorana zero modes with potential for scalable topological quantum computation, offering advantages over two-dimensional systems.

Contribution

It introduces quasi-one-dimensional quantum anomalous Hall structures as a new platform supporting localized Majorana modes with a larger topological regime than 2D systems.

Findings

Supports localized Majorana zero energy modes

Shows non-Abelian properties via time-dependent calculations

Networks can be fabricated for scalable quantum computation

Abstract

Quantum anomalous Hall insulator/superconductor heterostructures emerged as a competitive platform to realize topological superconductors with chiral Majorana edge states as shown in recent experiments [He et al. Science {\bf 357}, 294 (2017)]. However, chiral Majorana modes, being extended, cannot be used for topological quantum computation. In this work, we show that quasi-one-dimensional quantum anomalous Hall structures exhibit a large topological regime (much larger than the two-dimensional case) which supports localized Majorana zero energy modes. The non-Abelian properties of a cross-shaped quantum anomalous Hall junction is shown explicitly by time-dependent calculations. We believe that networks of such quasi-one-dimensional quantum anomalous Hall systems can be easily fabricated for scalable topological quantum computation.