Temperature and magnetic field dependent transport anisotropies in La0.7Ca0.3MnO3 films

Abstract

We report the temperature and field dependence of anisotropic magnetoresistance (AMR) in fully strained tetragonal thin films of the colossal magnetoresistance manganite La0.7Ca0.3MnO3. The behavior of the AMR is very different from that found in conventional metallic alloys. Its magnitude is peaked near the Curie temperature TC and becomes small at low temperature. It has two distinct symmetry components: one twofold symmetric about the transport current direction dominant near TC, the other fourfold symmetric with symmetry axes of the crystal, appearing at low temperature.