From Coherent Modes to Turbulence and Granulation of Trapped Gases

摘要: The process of exciting the gas trapped bosons from an equilibrium initial state to strongly nonequilibrium states is described as a procedure symmetry restoration caused by external perturbations. Initially, cooled down such low temperatures, when practically all atoms are in Bose-Einstein condensed state, which implies broken global gauge symmetry. Excitations realized either imposing alternating fields, modulating trapping potential and shaking cloud atoms, or it can be done varying atomic interactions means Feshbach resonance techniques. Gradually increasing amount energy pumped into system, strengthening modulation amplitude excitation time, produces series states, with growing fraction for restored. In this way, condensed, excited where normal completely restored process, starting regular superfluid passes through vortex superfluid, turbulent heterophase granular fluid, chaotic fluid regime. Both theoretical experimental studies presented.