Coulomb-interaction-induced Majorana edge modes in nanowires

TL;DR

This paper demonstrates that Majorana edge modes can emerge in semiconducting nanowires purely due to Coulomb interactions and orbital effects, without the need for spin-orbit coupling, magnetic fields, or superconductivity.

Contribution

It reveals a novel mechanism for Majorana modes arising from Coulomb interactions and orbital physics in nanowires, independent of traditional requirements.

Findings

Majorana modes appear in strongly correlated nanowires with rotational symmetry.

These modes exist without spin-orbit coupling, magnetic fields, or superconductivity.

The energy gap is comparable to that in conventional topological systems.

Abstract

We show that Majorana edge modes appear in a strongly correlated phase of semiconducting nanowires with discrete rotational symmetry in the cross section. These modes exist in the absence of spin-orbit coupling, magnetic fields and superconductivity. They appear purely due to the combination of the three-dimensional Coulomb interaction and orbital physics, which generates a fermionic condensate exhibiting a topological ground state degeneracy in a sector of the spectrum which is gapped to continuum modes. The gap can be comparable in magnitude to the topological superconducting gap in other solid-state candidate systems for Majorana edge modes, and may similarly be probed via tunnel spectroscopy.