Interaction-engineering and liquid-crystalline phases of ultracold atomic systems
Speaker: Dr. Sarang Gopalakrishnan, Harvard University
Department: Electrical Engineering
Location: Engineering Quadrangle B205
Date/Time: Tuesday, January 22, 2013, 4:00 p.m. - 5:00 p.m.
The intrinsic interactions between ultracold atoms are typically well described by an s-wave scattering length; thus, they are spatially isotropic and featureless. However, interatomic interactions of tunable range and structure can be engineered using auxiliary degrees of freedom, such as optical cavity modes. We show that the interactions mediated by a multimode optical cavity can give rise to a range of phases including a quantum liquid crystal (a super-smectic phase) and a spin glass . We then discuss how interactions with nontrivial structure emerge as a consequence of renormalization in spin-orbit coupled Bose gases, and how this emergent interaction structure governs the liquid-crystalline low-temperature phases of such systems .
 Sarang Gopalakrishnan, B.L. Lev, and P.M. Goldbart, Nature Physics 5, 845 (2009); Phys. Rev. Lett. 107, 277201 (2011).
 Sarang Gopalakrishnan, A. Lamacraft, and P.M. Goldbart, Phys. Rev. A 84, 061604(R) (2011).