Observation of many-body localization in a one-dimensional system with single-particle mobility edge

TL;DR

This paper experimentally investigates many-body localization in a one-dimensional quasiperiodic system with a single-particle mobility edge, revealing signatures of MBL and comparing with models lacking an intermediate phase.

Contribution

It provides the first experimental evidence of MBL in a system with a mobility edge and compares the dynamics with models without an intermediate phase.

Findings

Clear signatures of MBL in deep localized regimes

Differences observed compared to the Aubry-André model

Insights into the role of mobility edges in MBL

Abstract

We experimentally study many-body localization (MBL) with ultracold atoms in a weak one-dimensional quasiperiodic potential, which in the noninteracting limit exhibits an intermediate phase that is characterized by a mobility edge. We measure the time evolution of an initial charge density wave after a quench and analyze the corresponding relaxation exponents. We find clear signatures of MBL, when the corresponding noninteracting model is deep in the localized phase. We also critically compare and contrast our results with those from a tight-binding Aubry-Andr\'{e} model, which does not exhibit a single-particle intermediate phase, in order to identify signatures of a potential many-body intermediate phase.