Speaker
Prof.
Qi Zhou
(The Chinese University of Hong Kong)
Description
The recent realization of synthetic gauge fields for ultra
cold atoms provides physicists exciting opportunities to
investigate the interplay between two fundamental phenomena
in nature, Bose-Einstein condensation and spin-orbit
coupling. In this talk, I will discuss a novel effect of
spin-orbit coupling in bosonic systems, namely, it can
destroy a high-dimensional condensate even at sufficiently
low temperatures. This effect will be first demonstrated
using simple examples of non-interacting bosons, which
highlight the underlying physics that spin-orbit coupling
qualitatively changes the single-particle Density of States
at low energies. I will then turn to interacting systems,
where a condensate is stabilized by interaction at zero
temperature. On the other hand, condensate depletion is
significantly enhanced by spin-orbit coupling. Particularly,
thermal depletion becomes divergent when spin-orbit coupling
becomes isotropic and interaction is spin-independent. This
leads to the disappearance of a three-dimensional condensate
at any finite temperature, and suggests an interesting
routine to suppress the long-range order in weakly
interacting atomic systems via spin-orbit coupling. I will
also briefly discuss how spin-orbit coupling may
fundamentally change the properties of low-dimensional bosons.
Primary author
Prof.
Qi Zhou
(The Chinese University of Hong Kong)
