Periodically Driving a Many-Body Localized Quantum System

TL;DR

This study experimentally investigates how a periodically driven many-body localized quantum system transitions between localized and ergodic phases, revealing a dynamical phase transition influenced by drive frequency and strength.

Contribution

It provides the first experimental evidence of a dynamical phase transition in a driven many-body localized system, supported by numerical simulations and Floquet Hamiltonian analysis.

Findings

Localized phase at high drive frequencies

Ergodic phase at low drive frequencies

Dynamical phase transition dependent on drive parameters

Abstract

We experimentally study a periodically driven many-body localized system realized by interacting fermions in a one-dimensional quasi-disordered optical lattice. By preparing the system in a far-from-equilibrium state and monitoring the remains of an imprinted density pattern, we identify a localized phase at high drive frequencies and an ergodic phase at low ones. These two distinct phases are separated by a dynamical phase transition which depends on both the drive frequency and the drive strength. Our observations are quantitatively supported by numerical simulations and are directly connected to the change in the statistical properties of the effective Floquet Hamiltonian.