Synthesizing Majorana zero-energy modes in a periodically gated quantum wire

TL;DR

This paper proposes a method to create Majorana zero-energy modes in a one-dimensional quantum wire using periodic electric gating and spin-orbit interactions, advancing quantum computing research.

Contribution

It introduces a novel all-electric scheme employing periodic Rashba modulation and electron interactions to engineer topological superconductivity in quantum wires.

Findings

The scheme enables Fermi level crossing with a single spin-split band.

Electron-electron and Dresselhaus interactions open a topological gap.

Potential implementation in cold atom systems with Feshbach molecules.

Abstract

We explore a scheme for engineering a one-dimensional spinless p-wave superconductor hosting unpaired Majorana zero-energy modes, using an all-electric setup with a spin-orbit coupled quantum wire in proximity to an s-wave superconductor. The required crossing of the Fermi level by a single spin-split energy band is ensured by employing a periodically modulated Rashba interaction, which, assisted by electron-electron interactions and a uniform Dresselhaus interaction, opens a gap at two of the spin-orbit shifted Fermi points. While an implementation in a hybrid superconductor-semiconductor device requires improvements upon present-day capabilities, a variant of our scheme where spin-orbit-coupled cold fermions are effectively proximity-coupled to a BEC reservoir of Feshbach molecules may provide a ready-to-use platform.