Abstract
Interacting quantum gases exhibit superfluidity properties, such as the existence of a critical velocity for the creation of excitations or the appearance of quantum vortices in a rotating superfluid. The absence of viscosity allows, in a perfectly annular trap, the establishment of a permanent flow, whose velocity has a quantified circulation. In this seminar, I will present recent theoretical and experimental results involving (these) rotating quantum gases in two extreme situations. On the one hand, I will discuss the dissipation mechanisms of an elementary permanent current of a one-dimensional ring gas if a potential barrier is introduced at a point of the ring. Secondly, I will present the experimental realization of a quantum gas whose annular shape is due to its largely supersonic rotation in a bubble-shaped magnetic trap.
