Modulated Floquet Topological Insulators

TL;DR

This paper explores how spatially varying periodic driving in Floquet topological insulators creates localized states and currents, drawing analogies to superconductors, and proposes experimental setups for light-induced effects.

Contribution

It introduces the concept of modulated Floquet topological insulators with spatial variations, leading to new localized states and potential experimental applications.

Findings

Localized quasi-stationary states at potential nodes

Fractionalized excitations at vortices

Light-induced currents in the system

Abstract

Floquet topological insulators are topological phases of matter generated by the application of time-periodic perturbations on otherwise conventional insulators. We demonstrate that spatial variations in the time-periodic potential lead to localized quasi-stationary states in two-dimensional systems. These states include one-dimensional interface modes at the nodes of the external potential, and fractionalized excitations at vortices of the external potential. We also propose a setup by which light can induce currents in these systems. We explain these results by showing a close analogy to px+ipy superconductors.