Exploring the many-body localization transition in two dimensions

TL;DR

This paper reports the first experimental observation of a many-body localization transition in a two-dimensional disordered bosonic system, providing insights into non-thermalizing quantum phases beyond classical simulation capabilities.

Contribution

It demonstrates the existence and characterization of many-body localization in 2D, using single-site measurements to observe diverging length scales near the transition.

Findings

Evidence of a localization transition in 2D bosonic systems

Observation of diverging length scale approaching the transition

First experimental demonstration in a regime inaccessible to classical simulations

Abstract

One fundamental assumption in statistical physics is that generic closed quantum many-body systems thermalize under their own dynamics. Recently, the emergence of many-body localized systems has questioned this concept, challenging our understanding of the connection between statistical physics and quantum mechanics. Here we report on the observation of a many-body localization transition between thermal and localized phases for bosons in a two-dimensional disordered optical lattice. With our single site resolved measurements we track the relaxation dynamics of an initially prepared out-of-equilibrium density pattern and find strong evidence for a diverging length scale when approaching the localization transition. Our experiments mark the first demonstration and in-depth characterization of many-body localization in a regime not accessible with state-of-the-art simulations on classical computers.