Floquet Chern Vector Topological Insulators in Three Dimensions

TL;DR

This paper introduces a theoretical and numerical framework for three-dimensional Floquet topological insulators characterized by a Chern vector, achieved through phase-delayed temporal interactions that break time-reversal symmetry.

Contribution

It demonstrates the realization of 3D Chern vector topological insulators using Floquet engineering, revealing robust surface states and breaking time-reversal symmetry in a lattice model.

Findings

Observation of unidirectional surface states without backscattering

Numerical evidence of Chern numbers in all spatial dimensions

Effective gauge field induced by Floquet interactions

Abstract

We theoretically and numerically investigate Chern vector insulators and topological surface states in a three-dimensional lattice, based on phase-delayed temporal-periodic interactions within the tight-binding model. These Floquet interactions break time-reversal symmetry, effectively inducing a gauge field analogous to magnetic flux. This gauge field results in Chern numbers in all spatial dimensions, collectively forming the Chern vector. This vector characterizes the topological phases and signifies the emergence of robust surface states. Numerically, we observe these states propagating unidirectionally without backscattering on all open surfaces of the three-dimensional system. Our work paves the way for breaking time-reversal symmetry and realizing three-dimensional Chern vector topological insulators using temporal-periodic Floquet techniques.