Emergence of a soliton gas out of 3D turbulence in a binary Bose-Einstein condensate

Bose-Einstein condensates (BECs) offer a versatile platform for studying the interplay between turbulence and solitons in nonlinear quantum fluids. In our experiments, we generate counterflow between two spin components of a dilute-gas BEC in an elongated trap geometry. We observe that for suitably chosen parameters, this can induce strong turbulence in the BEC. To explore the underlying dynamics, we first investigate the effective drag force arising from the turbulent counterflow between the two superfluid components. When the driven counterflow is removed, the turbulence gradually decays, evolving into a disordered ensemble of solitons. We investigate the evolution of 3D turbulence into a quasi-one-dimensional soliton gas. These results establish a new experimental pathway for probing nonlinear hydrodynamics in binary superfluids.