Helical Dirac-Majorana interferometer in a superconductor-topological insulator sandwich structure

TL;DR

This paper proposes a novel helical Dirac-Majorana interferometer in a superconductor-topological insulator heterostructure, enabling direct measurement of helical Majorana modes, with potential realization in existing materials like Bi2Se3.

Contribution

It introduces a new interferometer design in a superconductor-topological insulator system to detect helical Majorana modes, advancing experimental approaches in topological quantum computing.

Findings

Existence of a topological superconducting phase with helical Majorana edge modes.

Proposal of a helical Dirac-Majorana interferometer for direct detection.

Feasibility of realizing the structure with Bi2Se3 or Bi2Te3 thin films.

Abstract

In the heterostructure composed of a topological insulator sandwiched by two s-wave superconductors, the time reversal invariant topological superconducting phase, possessing helical Majorana edge modes, is found to exist when the two s-wave superconductors form a Josephson junction with a pi phase shift. Based on such a heterostructure, a helical Dirac-Majorana interferometer is proposed to directly measure a unique transport signature of the helical Majorana modes. Furthermore, we envision how our proposal can be realized on the basis of existing materials such as Bi2Se3 or Bi2Te3 thin films.