From 3D turbulence to a 1D solitons gas: relaxation dynamics in a binary BEC

By utilizing a Bose–Einstein condensate (BEC) as a highly controllable quantum fluid, we investigate the interplay between turbulence and solitonic excitations in superfluid systems. In our experiments, we drive counterflow between two spin components of a dilute-gas BEC using a magnetic gradient. The driven counterflow induces modulational instability resulting in binary, three-dimensional, quantum turbulence. We then investigate how this turbulent superfluid relaxes in a quasi-one-dimensional trap geometry into a disordered ensemble of solitons. Using Fourier-based analysis, we characterize the transition from 3D turbulence toward the realization of a 1D soliton gas. Our results provide a new experimental framework for studying nonlinear superfluid hydrodynamics, investigating the link between turbulence and soliton gases.