Floquet dynamical quantum phase transitions in periodically quenched systems

TL;DR

This paper investigates Floquet dynamical quantum phase transitions in periodically driven one-dimensional systems with chiral symmetry, revealing multiple DQPTs, quantized topological order parameters, and potential for experimental realization and Floquet engineering.

Contribution

It systematically explores Floquet DQPTs in a class of periodically quenched systems, linking DQPTs to topological invariants and demonstrating their occurrence in a realizable lattice model.

Findings

Multiple Floquet DQPTs occur within a single driving period.

Quantized jumps in dynamical topological order parameters accompany DQPTs.

Rich Floquet topological phases are identified in the lattice model.

Abstract

Dynamical quantum phase transitions (DQPTs) are characterized by nonanalytic behaviors of physical observables as functions of time. When a system is subject to time-periodic modulations, the nonanalytic signatures of its observables could recur periodically in time, leading to the phenomena of Floquet DQPTs. In this work, we systematically explore Floquet DQPTs in a class of periodically quenched one-dimensional system with chiral symmetry. By tuning the strength of quench, we find multiple Floquet DQPTs within a single driving period, with more DQPTs being observed when the system is initialized in Floquet states with larger topological invariants. Each Floquet DQPT is further accompanied by the quantized jump of a dynamical topological order parameter, whose values remain quantized in time if the underlying Floquet system is prepared in a gapped topological phase. The theory is demonstrated in a piecewise quenched lattice model, which possesses rich Floquet topological phases and is readily realizable in quantum simulators like the nitrogen-vacancy center in diamonds. Our discoveries thus open a new perspective for the Floquet engineering of DQPTs and the dynamical detection of topological phase transitions in Floquet systems.