Probing superfluidity of periodically trapped ultracold atoms in a cavity by transmission spectroscopy

TL;DR

This paper investigates how transmission spectroscopy in a cavity can be used to probe the superfluidity of ultracold atoms arranged periodically, revealing the superfluid fraction through cavity transmission and reflection properties.

Contribution

It introduces a method to estimate the superfluid fraction of ultracold atoms in a cavity by analyzing transmission and reflection spectra, linking optical response to superfluid properties.

Findings

Cavity acts as a Lorentzian filter at minimum superfluid fraction.

Cavity fully reflects input at maximum superfluid fraction.

Superfluid fraction can be estimated from transmission/reflection ratio.

Abstract

We study a system of periodic Bose condensed atoms coupled to cavity photons using the input-output formalism. We show that the cavity will either act as a through pass Lorentzian filter when the superfluid fraction of the condensate is minimum or completely reflect the input field when the superfluid fraction is maximum. We show that by monitoring the ratio between the transmitted field and the reflected field, one can estimate the superfluid fraction.