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

Abstract

We study a system of periodic Bose-condensed atoms coupled to cavity photons using the input-output formalism of [14]. We show for the first time 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. © 2009 Versita Warsaw and Springer-Verlag Berlin Heidelberg.