Vortex dynamics in superfluids: Cyclotron-type motion.

Vortex dynamics in superfluids is investigated in the framework of the nonlinear Schrödinger equation. The natural motion of the vortex is of cyclotron type, whose frequency is found to be on the order of phonon velocity divided by the coherence length, and may be heavily damped due to phonon radiation. Trapping foreign particles into the vortex core can reduce the cyclotron frequency and make the cyclotron motion underdamped. The density fluctuations can follow the vortex motion adiabatically within the phonon wave length at the cyclotron frequency, which results in a further downward renormalization of the cyclotron frequency. We have also discussed applications on the dynamics of vortices in superconducting films. PACS numbers: 64.40.Mj, 67.40.Db, 67.40.Rp, 67.40.Vs, 74.60.Ge