Comunicazione
Dissipative vortex dynamics in homogeneous fermionic superfluids.
Grani N., Hernández-Rajkov D., Daix C., Inguscio M., Xhani K., Scazza F., Del Pace G., Kwon W., Roati G.
In superfluid and superconducting systems, the absence of viscosity and resistance gives the possibility to sustain persistent currents. However, the emergence of quantized vortices can affect this property. In particular, their motion can lead to dissipation even in these types of systems via phase-slippage processes. In our system we excite persistent currents in an annular fermionic superfluid and we observe the role of vortices in the current decay process in the presence of impurity. Moreover we study the dissipation process underlying the vortex dynamics by exciting on demand vortices configurations in a homogeneous disk with a high control over their position. In particular we probe dissipation effects by tracking the vortex trajectories in two simple cases: a vortex dipole and a single vortex moving in a background superflow.