Nucleation of Vortices by Rapid Thermal Quench

By numerical and analytical study of the time-dependent Ginzburg-Landau equation we show that vortex nucleation in superfluid {sup 3}He by rapid thermal quench in the presence of superflow is dominated by a transverse instability of the moving normal-superfluid interface. Exact expressions for the instability threshold as a function of supercurrent density and the front velocity are found. {copyright} {ital 1999} {ital The American Physical Society}