Density Resolved Wave Packet Spreading in Disordered Gross-Pitaevskii Lattices

TL;DR

This study investigates wave packet spreading in disordered Gross-Pitaevskii lattices, revealing regimes of weak and strong chaos, a disorder-induced insulating phase, and the impact of Lifshits tails on spreading dynamics.

Contribution

It introduces a novel density-resolved analysis of wave packet spreading and maps the regimes of chaos and insulating phases in disordered GP lattices.

Findings

Strong chaos leads to subdiffusive spreading over decades

Disorder causes a renormalization of the ground state

Lifshits tails induce a phase with slowed wave packet spreading

Abstract

We perform novel energy and norm density resolved wave packet spreading studies in the disordered Gross-Pitaevskii (GP) lattice to confine energy density fluctuations. We map the locations of GP regimes of weak and strong chaos subdiffusive spreading in the 2D density control parameter space and observe strong chaos spreading over several decades. We obtain a renormalization of the ground state due to disorder, which allows for a new disorder-induced phase of disconnected insulating puddles of matter due to Lifshits tails. Inside this Lifshits phase, the wave packet spreading is substantially slowed down.