Anomalous anisotropic magnetoresistance in Pr0.67Sr0.33MnO3 thin films

Abstract

Anisotropic magnetoresistance (AMR) in strained Pr0.67Sr0.33MnO3 thin films has been studied by measuring the resistance as a function of the angle between the applied magnetic field direction and the film normal with the current always perpendicular to the magnetic field. The results show that both compressive- and tensile-strained ultrathin films (50–150 Å) exhibit unusually large AMR, but with opposite signs. In contrast, the almost strain free films show much smaller AMR over all the temperature and field ranges studied. The AMR decreases rapidly as the film thickness increases due to the gradual release of strain.