Topological Floquet Phases in Driven Coupled Rashba Nanowires

TL;DR

This paper explores how periodically-driven Rashba nanowire arrays can host various topological phases, including fractionalized states, by tuning non-equilibrium Floquet states and considering strong electron interactions.

Contribution

It introduces a framework for realizing and analyzing topological Floquet phases, including fractional regimes, in driven coupled Rashba nanowires.

Findings

Identification of Floquet topological insulator and Weyl semimetal phases.

Prediction of fractionalized edge modes with fractional charge.

Demonstration of tunability of topological phases via periodic driving.

Abstract

We consider periodically-driven arrays of weakly coupled wires with conduction and valence bands of Rashba type and study the resulting Floquet states. This non-equilibrium system can be tuned into non-trivial phases such as of topological insulators, Weyl semimetals, and dispersionless zero-energy edge mode regimes. In the presence of strong electron-electron interactions, we generalize these regimes to the fractional case, where elementary excitations have fractional charges $e/m$ with $m$ being an odd integer.