Epitaxial La 0.9Ca 0.1MnO 3 films grown on vicinal cut substrates for the investigation of resistivity and thermoelectric anisotropy

Abstract

La 0.9Ca 0.1MnO 3 thin films have been grown on 5° vicinal cut SrTiO 3 (1 0 0) substrates by pulse laser deposition. The single phase and the epitaxial growth aligned to the c-axis of vicinal cut substrates have been studied by X-ray diffraction analysis. The resistivity versus temperature measurements along and perpendicular to the substrate tilted direction show that the resistivity anisotropy ρ c / ρ ab is 22.44 at room temperature, originating from the intrinsic Jahn–Teller distortion, strain and defects. The Seebeck coefficient anisotropy Δ S of 0.317 μV K −1 attained by laser-induced theroelectric voltages experiment has coincidence with the resistivity anisotropy, which is interpreted by the Mott band theory for Seebeck coefficient approximation.