Particle-hole symmetric localization in optical lattices using time modulated random on-site potentials

TL;DR

This paper proposes a method to realize particle-hole symmetric localization in optical lattices by modulating on-site potentials, enabling control over localization properties and mimicking random hopping models.

Contribution

It introduces a technique to simulate pure random hopping models in ultracold atoms through frequency-controlled modulation of disordered potentials.

Findings

Gradual increase of oscillation frequency tunes the system from Anderson insulator to random hopping model.

Diverging localization length occurs at the band center in the random hopping regime.

The method enables experimental realization of particle-hole symmetric localization phenomena.

Abstract

The random hopping models exhibit many fascinating features, such as diverging localization length and density of states as energy approaches the bandcenter, due to its particle-hole symmetry. Nevertheless, such models are yet to be realized experimentally because the particle-hole symmetry is easily destroyed by diagonal disorder. Here we propose that a pure random hopping model can be effectively realized in ultracold atoms by modulating a disordered onsite potential in particular frequency ranges. This idea is motivated by the recent development of the phenomena called "dynamical localization" or "coherent destruction of tunneling". Investigating the application of this idea in one dimension, we find that if the oscillation frequency of the disorder potential is gradually increased from zero to infinity, one can tune a non-interacting system from an Anderson insulator to a random hopping model with diverging localization length at the band center, and eventually to a uniform-hopping tight-binding model.