Direct reconstruction of the band structure of a 1D optical lattice with thermal atoms

TL;DR

This paper introduces a straightforward method to directly reconstruct the band structure of a 1D optical lattice using thermal atoms, enabling precise calibration and single-shot lattice depth estimation.

Contribution

The authors present a novel technique combining experimental imaging and numerical calculations to reconstruct the band structure from thermal atom momentum distributions.

Findings

Successful reconstruction of the 1D optical lattice band structure.

Demonstration of a single-shot method for lattice depth estimation.

Validation of the method as a precise calibration tool.

Abstract

We report on a simple method to reconstruct the band structure of a 1D optical lattice using a thermal cloud with a momentum spread of about two-photon recoils. We image the momentum distribution of a thermal cloud exposed to a standing wave potential using time-of-flight absorption images and observe unique features. With the support of numerical calculations, we explain their appearance and show how they can be used to reconstruct the full band-structure directly. While this can serve as a precise lattice depth calibration tool, we additionally propose a method to estimate the lattice depth in a single-shot manner.