Laser processed channels of easy vortex motion in YBa 2Cu 3O 7-δ films

Abstract

Vortex dynamics in laser-patterned channels for easy motion in YBa2 Cu3 O7-δ thin-film bridges has been investigated by electric transport and magneto-optical measurements. It has been found that the laser-writing technique, relying on selective deoxygenation of the illuminated areas of YBa2 Cu3 O7-δ films, enables manufacturing of channels with the decreased field of the first penetration and pinning strength. Current-induced vortices confined in such channels move coherently within a limited temperature and bias ranges. Coherence in vortex motion was confirmed by the direct observation of self-resonant, Josephson-like current steps on the bridge current-voltage characteristics. © 2005 American Institute of Physics.