Probing Neutral Majorana Fermion Edge Modes with Charge Transport

TL;DR

This paper proposes experimental setups to detect and manipulate neutral Majorana fermion edge modes on topological insulators using charge transport and interferometry, advancing the understanding of topological quantum states.

Contribution

It introduces novel experimental designs, including a Majorana interferometer and a controllable point contact, to probe neutral Majorana fermions via charge transport methods.

Findings

Design of a Majorana interferometer for Z_2 phase detection

Proposal of a superconducting junction point contact with phase-controlled transmission

Feasibility analysis using Bi_2 Se_3 topological insulator

Abstract

We propose two experiments to probe the Majorana fermion edge states that occur at a junction between a superconductor and a magnet deposited on the surface of a topological insulator. Combining two Majorana fermions into a single Dirac fermion on a magnetic domain wall allows the neutral Majorana fermions to be probed with charge transport. We will discuss a novel interferometer for Majorana fermions, which probes their Z_2 phase. This setup also allows the transmission of neutral Majorana fermions through a point contact to be measured. We introduce a point contact formed by a superconducting junction and show that its transmission can be controlled by the phase difference across the junction. We discuss the feasibility of these experiments using the recently discovered topological insulator Bi_2 Se_3.