Phase dependent loading of Bloch bands and Quantum simulation of relativistic wave equation predictions with ultracold atoms in variably shaped optical lattice potentials

TL;DR

This paper demonstrates how ultracold atoms in variably shaped optical lattices can simulate relativistic physics, using a Raman technique to load atoms into specific Bloch bands and showcasing phenomena like Klein tunneling and Veselago lensing.

Contribution

It introduces a Raman loading technique for selective band population and presents experimental analogs of relativistic phenomena with ultracold atoms.

Findings

Successful selective loading into desired Bloch bands near band crossings

Observation of Klein tunneling analog in ultracold atoms

Demonstration of Veselago lensing with quasirelativistic atoms

Abstract

The dispersion relation of ultracold atoms in variably shaped optical lattices can be tuned to resemble that of a relativistic particle, i.e. be linear instead of the usual nonrelativistic quadratic dispersion relation of a free atom. Cold atoms in such a lattice can be used to carry out quantum simulations of relativistic wave equation predictions. We begin this article by describing a Raman technique that allows to selectively load atoms into a desired Bloch band of the lattice near a band crossing. Subsequently, we review two recent experiments with quasirelativistic rubidium atoms in a bichromatic lattice, demonstrating the analogs of Klein tunneling and Veselago lensing with ultracold atoms respectively.