Effect of tilted columnar defects on vortex pinning in YBa2Cu3Ox films - art. no. 184518

We have studied the effect of tilted columnar defects on vortex pinning in YBa2Cu3Ox thin films. The usual directional dependence of vortex pinning wh en a magnetic field is aligned to the columnar defects and the matching eff ect as a function of field are observed. In addition to the regular behavio r in resistivity and critical current an additional pinning feature is obse rved when the field is aligned close to the ab plane. From the trapping ang le of vortices the effective pinning strength of the columnar defects is fo und to be substantially higher than that of the twin boundary pinning, It i s also observed that the enhancement of vortex pinning is still significant up to theta (d) = 40 degrees for fields parallel to the c axis consistent with the single crystal results of the enhanced vortex pinning even by the high-angle crossed defects.