Pressure and Size Dependence of Roton Emission and Vortex Creation by Moving Objects in He II in T to 0 Limit: Generalized Nonlocal Gross-Pitaevskii Model
This study uses a generalized, nonlocal Gross-Pitaevskii model to numerically investigate how pressure and object size affect roton emission and vortex nucleation by moving objects in superfluid Helium II at zero temperature. The research successfully links the model's dispersion relation to experimental data across varying pressures (0 to 24 bar), finding that roton critical velocities decrease with pressure while vortex nucleation velocities increase.