Dissipative dynamics of quantized vortices in strongly interacting Fermi gases

Quantum vortices in a superfluid have fundamental differences compared to classical vortices, especially in their dissipative dynamics due to lack of viscosity. We study the dissipation of quantized vortices in ⁶Li fermionic superfluids confined in uniform and planar geometry so that a vortex here can be considered as a two-dimensional vortex. To create a vortex and an antivortex, we apply a repulsive obstacle beam focused on the cloud and translate it with a velocity above a critical value. We will first report our measurements on the characteristics of a single dipole across the BEC-BCS crossover. Then, we will show collisional dynamics of a few vortices, which constitutes the fundamentals of many-body vortex dynamics in quantum fluids. Finally, we will address dissipation in vortex collisions, which is inherently different from dissipation in a single dipole case.