Frequency dependent conductivity of vortex cores in type II superconductors
Abstract
Recent experiments by Karraï et al. probed vortices in YBa _{2}Cu _{3}O _{7} at frequencies near the “minigap” between discrete core states, Δ ^{2}/ E_{F}. E_{F} is the Fermi energy and Δ is the bulk energy gap. Here we calculate the conductivity, σ(ω), of vortices using a novel, microscopic description of single vortex dynamics based on the BogoliubovdeGennes equations and selfconsistency through the gap equation. It is applicable to the low temperature, clean, type II limit. An equation of motion for vortex cores valid at nonzero frequencies, including Magnus, drag, and pinning forces, is derived. The cyclotron resonance as well as structure at the minigap appear in σ(ω). The expected dipole transition between localized states is hidden because the vortex is a selfconsistent potential. Unless translation invariance is broken, single particle properties are invisible to a long wavelength probe. Upon adding drag and pinning, dissipation near h̵hω≈Δ ^{2}/ E_{F} appears.
 Publication:

Physica C Superconductivity
 Pub Date:
 August 1993
 DOI:
 10.1016/09214534(93)90447X
 arXiv:
 arXiv:condmat/9208020
 Bibcode:
 1993PhyC..213..305H
 Keywords:

 Condensed Matter
 EPrint:
 35 pages plus six pages of figures: not included but postscript files available upon request. Send requests and other comments to: hsu@crtbt.polycnrsgre.fr. Revtex