Induced p-wave superconductivity without spin-orbit interactions

TL;DR

This paper demonstrates that p-wave superconductivity and Majorana modes can be induced in a two-band system through antisymmetric hybridization and inter-band interactions, without relying on spin-orbit coupling, opening new avenues for quantum computing.

Contribution

It introduces a novel mechanism for inducing p-wave superconductivity via hybridization and inter-band interactions, bypassing the need for spin-orbit effects.

Findings

Induced p-wave superconductivity in a non-interacting band.

Presence of four Majorana modes at the ends of a wire.

Long-range correlations enabling protected qubits.

Abstract

The study of Majorana fermions is of great importance for the implementation of a quantum computer. These modes are topologically protected and very stable. It is now well known that a p-wave superconducting wire can sustain, in its topological non-trivial phase, Majorana quasi-particles at its ends. Since this type of superconductor is not found in nature, many methods have been devised to implement it. Most of them rely on the spin-orbit interaction. In this paper we study the superconducting properties of a two-band system in the presence of antisymmetric hybridization. We consider inter-band attractive interactions and also an attractive interaction in one of the bands. We show that superconducting fluctuations with p-wave character are induced in the non-interacting band due to the combined effects of inter-band coupling and hybridization. In the case of a wire, this type of induced superconductivity gives rise to four Majorana modes at its ends. The long range correlation between the different charge states of these modes offers new possibilities for the implementation of protected q-bits.