Quantum phase transitions and a disorder-based filter in a Floquet system

TL;DR

This paper explores the rich topological phases of a driven honeycomb lattice model, analyzing their robustness against disorder and proposing a disorder-based filter for edge states in Floquet systems.

Contribution

It identifies various topological phases in a driven honeycomb lattice and introduces a disorder-based filter leveraging their robustness.

Findings

Rich mixture of weak and strong topological phases identified.

Topological phases show robustness against spatial disorder.

Proposed a practical filter for edge states using existing experimental techniques.

Abstract

Two-dimensional periodically-driven topological insulators have been shown to exhibit numerous topological phases, including ones which have no static analog, such as anomalous Floquet topological phases. We study a two dimensional model of spinless fermions on a honeycomb lattice with periodic driving. We show that this model exhibits a rich mixture of weak and strong topological phases, which we identify by computing their scattering matrix invariants. Further, we do an in-depth analysis of these topological phases in the presence of spatial disorder and show the relative robustness of these phases against imperfections. Making use of this robustness against spatial disorder, we propose a filter which allows the passage of only edge states, and which can be realized using existing experimental techniques.