Glassy disorder-induced effects in noisy dynamics of Bose-Hubbard and Fermi-Hubbard systems

TL;DR

This paper investigates how quenched disorder affects the dynamics of ultracold atom systems in optical lattices, revealing disorder-induced enhancements in entanglement and similar effects in bosonic and fermionic systems.

Contribution

It provides a detailed analysis of disorder effects on Bose-Hubbard and Fermi-Hubbard systems under noise, highlighting disorder-induced entanglement enhancement and the role of parameter statistics.

Findings

Disorder can enhance bipartite entanglement in weakly interacting bosonic systems.

Similar disorder effects are observed in fermionic systems.

Disorder effects remain consistent regardless of initial states.

Abstract

We address the effects of quenched disorder averaging in the time-evolution of systems of ultracold atoms in optical lattices in the presence of noise, imposed by of an environment. For bosonic systems governed by the Bose-Hubbard Hamiltonian, we quantify the response of disorder in Hamiltonian parameters in terms of physical observables, including bipartite entanglement in the ground state and report the existence of disorder-induced enhancement in weakly interacting cases. For systems of two-species fermions described by the Fermi-Hubbard Hamiltonian, we find similar results. In both cases, our dynamical calculations show no appreciable change in the effects of disorder from that of the initial state of the evolution. We explain our findings in terms the statistics of the disorder in the parameters and the behaviour of the observables with the parameters.