Abstract :
Enhancement of magnetoresistance (MR) has been achieved at room temperature in the perovskite La0.8Ba0.2MnO3 epitaxial thin films. It was found that these particular epitaxial thin films exhibit higher MR ratio than that of bulk material (21% at 270 K), i.e. 33% at 320 K for 400 Å thickness, 43% at 307 K for 650 Å, 45% at 298 K for 1000 Å and 48% at 267 K for 1300 Å under the magnetic field of 8000 Oe. The metal–insulator transition temperature and magnetoresistance strongly depend on the film thickness. The MR ratio of the La0.8Ba0.2MnO3 film at room temperature is remarkably large in comparison with that of other magnetoresistive oxides.