Rashba spin-orbit coupling and artificially engineered topological superconductors

TL;DR

This paper reviews the role of Rashba spin-orbit coupling in creating topological superconductors that host Majorana zero modes, which are promising for fault-tolerant quantum computing.

Contribution

It critically discusses how Rashba spin-orbit coupling enables the engineering of topological superconductors with Majorana modes for quantum computation.

Findings

RSOC is crucial for producing low-dimensional topological superconductors.

Increasing RSOC strength enhances the topological gap.

Topological superconductors with Majorana modes can enable fault-tolerant quantum computing.

Abstract

One of the most important physical effects in condensed matter physics is the Rashba spin-orbit coupling (RSOC), introduced in seminal works by Emmanuel Rashba. In this article, we discuss, describe, and review (providing critical perspectives on) the crucial role of RSOC in the currently active research area of topological quantum computation. Most, if not all, of the current experimental topological quantum computing platforms use the idea of Majorana zero modes as the qubit ingredient because of their non-Abelian anyonic property of having an intrinsic quantum degeneracy, which enables nonlocal encoding protected by a topological energy gap. It turns out that RSOC is a crucial ingredient in producing a low-dimensional topological superconductor in the laboratory, and such topological superconductors naturally have isolated localized midgap Majorana zero modes. In addition, increasing the RSOC strength enhances the topological gap, thus enhancing the topological immunity of the qubits to decoherence. Thus, Rashba's classic work on SOC may lead not only to the realization of localized non-Abelian anyons, but also fault tolerant quantum computation.