First-order quantum phase transition driven by rotons in a gaseous Bose-Einstein condensate irradiated by a laser

Abstract

O'Dell et al. in recent work [Phys. Rev. Lett. 90, 110402 (2003)] have proposed that laser-induced dipole-dipole interactions may drive a gaseous Bose-Einstein condensate to an instability against a periodic density modulation. We discuss the possibility that the instability is preceded by a first-order quantum phase transition to a modulated state.