arXiv:1110.6386 · Physical Review Letters
Quantum Dynamics of a Bose Superfluid Vortex
L. Thompson, Philip C. E. Stamp
Abstract
We derive a fully quantum-mechanical equation of motion for a vortex in a 2-dimensional Bose superfluid in the temperature regime where the normal fluid density ${\ensuremath{\rho}}_{n}(T)$ is small. The coupling between the vortex ``zero mode'' and the quasiparticles has no term linear in the quasiparticle variables---the lowest-order coupling is quadratic. We find that as a function of the dimensionless frequency $\stackrel{\texttildelow{}}{\ensuremath{\Omega}}=\ensuremath{\hbar}\ensuremath{\Omega}/{k}_{B}T$, the standard Hall-Vinen-Iordanskii equations are valid when $\stackrel{\texttildelow{}}{\ensuremath{\Omega}}\ensuremath{\ll}1$ (the ``classical regime''), but elsewhere, the equations of motion become highly retarded, with significant experimental implications when $\stackrel{\texttildelow{}}{\ensuremath{\Omega}}\ensuremath{\gtrsim}1$.