Observation of subdiffusive dynamic scaling in a driven and disordered box-trapped Bose gas

Résumé : We explore the dynamics of a tuneable box-trapped Bose gas under strong periodic forcing in the presence of weak disorder. In absence of interparticle interactions, the interplay of the drive and disorder results in an isotropic nonthermal momentum distribution that shows subdiffusive dynamic scaling, with sublinear energy growth and the universal scaling function captured well by a compressed exponential. For increasing interaction strength, the gas behavior crosses over to wave turbulence characterized by a power-law momentum distribution.