MAGNETIC VORTICES AND THERMOELECTRIC EFFECT IN A HOLLOW SUPERCONDUCTING CYLINDER

The question of a surface barrier which determines the behavior of a v ortex in a hollow superconducting cylinder of finite thickness in an e xternal magnetic field is discussed, taking into account magnetic flux quantization in the cavity. The behavior of magnetic vortices in a ho llow superconductor in the presence of a thermoelectric current is als o considered. Pairs of magnetic vortices with opposite magnetic field orientations (vortex-antivortex pairs) are generated by this current n ear T-c. The thermoelectric current dl-ives the antivortex (the vortex with oppositely directed field) out of the cylinder, whereas the vort ex is ejected into the cavity and remains on the inside cylinder surfa ce as a current. The number of magnetic flux quanta trapped inside the cylinder increases by one. The relation of this mechanism to the ''gi ant'' thermoelectric effect in hollow superconductors is discussed. (C ) 1997 American Institute of Physics.