MAGNETORESISTANCE OF A YBA2CU3O7 CORBINO DISK - PROBING GEOMETRICAL CONTRIBUTIONS TO THE UNCONVENTIONAL NORMAL-STATE MAGNETORESISTANCE OF HIGH-TEMPERATURE SUPERCONDUCTORS

Complementary measurements of geometrical effects in the normal-state magnetoresistance of YBa2CU3O7 thin films, patterned into a Corbino di sk, a square, and a strip-shaped sample, are reported. We observe a di fference between the Corbino and strip-sample magnetoresistances, whic h arises from bending of the current trajectories in the transverse ma gnetic field and equals the square of the Hall angle in YBa2Cu3O7. Thi s geometrical magnetoresistance component vanishes when the magnetic f ield is oriented parallel to the film. The geometrical magnetoresistan ce has also been found to be significant in square-shaped samples, and thus, has to be considered in magnetoresistance measurements of YBa2C u3O7 single crystals.