Floquet symmetry-protected topological phases in cold atomic systems

TL;DR

This paper explores two methods to realize symmetry-protected topological phases in cold atomic systems using periodic driving, demonstrating stable Floquet SPT phases and identifying experimental signatures and implementations.

Contribution

It introduces two approaches for creating Floquet SPT phases, including an equilibrium emulation and an intrinsically Floquet phase, with analysis of stability, signatures, and experimental realization.

Findings

Driven transverse-field Ising model can emulate equilibrium SPT phases.

Disorder-induced many-body localization prevents heating and stabilizes phases.

Protected edge modes are observable in Rydberg atom chains within experimental timescales.

Abstract

We propose and analyze two distinct routes toward realizing interacting symmetry-protected topological (SPT) phases via periodic driving. First, we demonstrate that a driven transverse-field Ising model can be used to engineer complex interactions which enable the emulation of an equilibrium SPT phase. This phase remains stable only within a parametric time scale controlled by the driving frequency, beyond which its topological features break down. To overcome this issue, we consider an alternate route based upon realizing an intrinsically Floquet SPT phase that does not have any equilibrium analog. In both cases, we show that disorder, leading to many-body localization, prevents runaway heating and enables the observation of coherent quantum dynamics at high energy densities. Furthermore, we clarify the distinction between the equilibrium and Floquet SPT phases by identifying a unique micromotion-based entanglement spectrum signature of the latter. Finally, we propose a unifying implementation in a one-dimensional chain of Rydberg-dressed atoms and show that protected edge modes are observable on realistic experimental time scales.