Rotons in gaseous Bose-Einstein condensates irradiated by a laser

TL;DR

This paper explores how laser-induced dipole-dipole interactions in a gaseous Bose-Einstein condensate can create a roton minimum in the excitation spectrum, similar to superfluid helium, with tunable properties.

Contribution

It demonstrates the theoretical possibility of inducing and controlling roton minima in BECs through laser parameters, expanding understanding of quantum fluid excitations.

Findings

Laser-induced dipole-dipole interactions produce a roton minimum.

The roton feature is tunable via laser intensity and frequency.

Behavior resembles that of superfluid helium II.

Abstract

A gaseous Bose-Einstein condensate (BEC) irradiated by a far off-resonance laser has long-range interatomic correlations caused by laser-induced dipole-dipole interactions. These correlations, which are tunable via the laser intensity and frequency, can produce a `roton' minimum in the excitation spectrum--behavior reminiscent of the strongly correlated superfluid liquid helium II.