Study of Matching Fields in Kagomé Patterned YBCO Thin Films

Superconducting YBCO thin films have been prepared by the pulsed laser deposition (PLD) technique. YBCO films have been patterned by kagomé antidot lattice. The optical lithography technique has been used to get the required pattern. We have studied the variation of the critical current with magnetic field in kagomé patterned YBCO films. The longitudinal critical current exhibits jumps which are found to be asymmetrically positioned in magnetic field. These steps are found mainly at nonmatching fields. Around the zero field limit the critical current remains independent of magnetic field. The impact of the DC current and ac-superposition in controlling the vortex motion in patterned film has been discussed.