Inelastic light scattering from a Mott insulator

TL;DR

This paper proposes using Bragg spectroscopy to measure the excitation spectrum and gap of a Mott insulator state in an atomic Bose gas within an optical lattice, providing a new experimental approach.

Contribution

It introduces a method to determine the Mott insulator's excitation gap via photon scattering rate measurements, including detailed calculations of the structure factor.

Findings

Calculated the structure factor considering selfenergy corrections

Showed how to extract the excitation gap from scattering measurements

Provided a theoretical framework for experimental detection

Abstract

We propose to use Bragg spectroscopy to measure the excitation spectrum of the Mott insulator state of an atomic Bose gas in an optical lattice. We calculate the structure factor of the Mott insulator taking into account both the selfenergy corrections of the atoms and the corresponding dressing of the atom-photon interaction. We determine the scattering rate of photons in the stimulated Raman transition and show that by measuring this scattering rate in an experiment, in particular the excitation gap of the Mott insulator can be determined.