Grain-Boundary Magnetoresistance of CrO2 Films Grown on TiO2-Buffered LaAlO3 Substrates

S. J. Liu；J. Y. Juang；K. H. Wu；T. M. Uen；Y. S. Gou；J.-Y. Lin

Chinese Journal of Physics

41卷4期（2003 / 08 / 01）

406 - 413

英文

The magnetic and magnetotransport properties of predominantly (110)-oriented CrO2 films grown on TiO2-buffered LaAlO3 substrates were investigated. The atomic force microscopic images revealed that the as-grown CrO2 films are granular. The magnetic measurements indicated that in-plane coercive fields are about 60 Oe and 100 Oe at 300 K and 7 K, respectively. The as-grown films are semiconductive below 75 K; a magnetoresistance with a △R/R0 ratio of -13 % in a magnetic field of 5 T was observed at 5 K, which is absent in high-quality epitaxial films. The coincidence between the coercive field and the peaks of the magnetoresistive loop measured at low temperatures indicates that spin-dependent scattering plays a crucial role in the transport properties.