Localization of cold atoms in state-dependent optical lattices via a Rabi pulse

TL;DR

This paper demonstrates a new method to realize Anderson localization in ultracold atoms using a Rabi pulse to create state-dependent disorder, leading to localized wavefunctions with exponential tails.

Contribution

It introduces a novel non-equilibrium approach to induce Anderson localization in ultracold atoms via Rabi pulse-driven state transfer and disorder creation.

Findings

Localization length increases with disorder strength.

Interaction strength influences localization differently than in equilibrium.

Wavefunctions exhibit exponential decay tails characteristic of Anderson localization.

Abstract

We propose a novel realization of Anderson localization in non-equilibrium states of ultracold atoms trapped in state-dependent optical lattices. The disorder potential leading to localization is generated with a Rabi pulse transfering a fraction of the atoms into a different internal state for which tunneling between lattice sites is suppressed. Atoms with zero tunneling create a quantum superposition of different random potentials, localizing the mobile atoms. We investigate the dynamics of the mobile atoms after the Rabi pulse for non-interacting and weakly interacting bosons, and we show that the evolved wavefunction attains a quasi-stationary profile with exponentially decaying tails, characteristic of Anderson localization. The localization length is seen to increase with increasing disorder and interaction strength, oppositely to what is expected for equilibrium localization.