Microscopic model for finite-temperature vortex dynamics in rotating superfluid helium

H. M. CATALDO

Horizons in World Physics. Volume 277

Nova Science Publishers

Lugar: New York; Año: 2011;

We have developed a Hamiltonian model for the dissipative dynamics of the Kelvin waves that propagate along a quantized vortex filament in helium II. Showing that such waves turn out to be damped and frequency-shifted by the effect of the scattering of thermal quasiparticles, we have extracted the relationship between such frequency damping and shift, and the longitudinal and transverse friction coefficients, respectively. Thus, we have derived formulas for such coefficients in the form of functionals of the vortex-quasiparticle scattering amplitude. Our expression for the longitudinal friction coefficient turns out to be equivalent to the Iordanskii formula, and utilizing a simple functional form for the scattering amplitude, an excellent agreement with experimental results up to temperatures about 1.5 K has been obtained. On the other hand, the  transverse friction coefficient is shown to vanish in the limit of a straight vortex in an infinite medium, but a more definite test on our formula should have to await until theoretical models for the scattering amplitude outside the phonon range have been formulated and additional experimental information has been obtained.