Relaxation of an out-of-equilibrium closed quantum systems: experimental observations of decay of turbulence and the stages to reach equilibrium

Starting with a Bose-Einstein Condensate of Rb atoms in equilibrium, the System is brought to turbulence and left to relax under the occurrence of reactions from the introduced excitations. The typical phenomena of the evolution to establishment of the turbulence states are observed. After excitation is removed, the system begins to relax, giving way to diverse phenomena such as the presence of non-thermal fixed points, pre-thermalization and finally equilibrium with or without the reconstitution of the condensate depending of the quantity of injected energy. The work paves the way for the study of the thermalization of an out-of-equilibrium many-body quantum system.