Manipulating Majorana fermions using supercurrents

TL;DR

This paper introduces a novel method to manipulate Majorana fermions using supercurrents in s-wave superconductors, enabling control over topological phases in quantum wires and insulator edges.

Contribution

It demonstrates that supercurrents can induce topological phase transitions and facilitate Majorana fermion manipulation, reducing the required Zeeman field in quantum wires.

Findings

Supercurrents can drive topological phase transitions.

Majorana fermions can be generated and manipulated via supercurrents.

Supercurrents reduce the critical Zeeman field needed for topological phases.

Abstract

Topological insulator edges and spin-orbit-coupled quantum wires in proximity to s-wave super- conductors can be tuned through a topological quantum phase transition by a Zeeman field. Here we show that a supercurrent flowing in the s-wave superconductor also drives such a transition. We propose to use this new mechanism to generate and manipulate Majorana fermions that localize at domain walls between topological and nontopological regions of an edge or wire. In quantum wires, this method carries the added benefit that a supercurrent reduces the critical Zeeman field at which the topological phase appears.