Principal Investigator :

Fabien Alet ()
LPT

Type of project : Disruptive Project

Date (start/end) : 2017 - 2019

     

       

Abstract

The subject of this proposal is the theoretical study of models of Many Body Localization (MBL), with the specific goal of modeling very recent experiments exhibiting this phenomenon. MBL, one of the hottest problems in quantum physics, addresses fundamental questions on how a disordered, strongly-interacting and closed quantum system can reach equilibrium. MBL has been even further highlighted by beautiful cold-atom systems where dynamical localization can be observed. In this project, we wish to develop new tools to provide quantitative answers to the new questions posed by these experiments.

In a first task, we will develop a computational technique (time-evolving method in a matrix product operator framework) to solve the problem of a 1d MBL system coupled to a bath, which is relevant for the cold-atomic systems. This will allow for instance to understand the dynamical (un)stability of MBL with respect to dissipation, which strength can be increased on purpose in the experiments.

In a second task, we will address the important question of how to experimentally distinguish an Anderson from a MBL insulator, in the context of the present cold-atom experiments. For this, we will build and compute a new observable, experimentally accessible, inspired by recent advances in quantum chaos theory.

Both tasks will imply state-of-the-art numerics on the out-of-equilibrum dynamics of strongly interacting disordered quantum models, with direct implications for current experiments.