Hall Effect due to channeled pinning potential in Nb thin films

We have studied the Magnetoresistance and Hall Effect in Nb superconducting thin films with triangular arrays of holes. Three different arrays of defects have been prepared with different orientations with respect to the current. Because vortex dynamics in the mixed state in type-II superconductors is strongly influenced by the pinning centers, a channeled pinning landscape is formed by the pinned vortices. It is suggested that the motion of interstitial vortices has great influence by the channel. When vortices propagate through these arrays, both the longitudinal and transversal voltages show cusp-like anomalies at matching fields. Vortices can be guided by the channel formed between pinned vortices. The longitudinal voltages are the same when there is a sign change of magnetic field. The longitudinal and transversal Hall voltages are dependent on the rotating angle of the arrays.