Magnetoresistance of a YBa2Cu3O7 Corbino disk: Probing geometrical contributions to the unconventional normal-state magnetoresistance of high-temperature superconductors

摘要

Complementary measurements of geometrical effects in the normal-state magnetoresistance of YBa2CU3O7 thin films, patterned into a Corbino disk, a square, and a strip-shaped sample, are reported. We observe a difference between the Corbino and strip-sample magnetoresistances, which arises from bending of the current trajectories in the transverse magnetic field and equals the square of the Hall angle in YBa2Cu3O7. This geometrical magnetoresistance component vanishes when the magnetic field is oriented parallel to the film. The geometrical magnetoresistance has also been found to be significant in square-shaped samples, and thus, has to be considered in magnetoresistance measurements of YBa2Cu3O7 single crystals. [References: 15]