Surface and transport studies on La0.7Ba0.3MnO3:SnO2 bilayer

Abstract We report on study of morphology, optical contrast and transport characteristics of La 0.7 Ba 0.3 MnO 3 (LBMO) manganite thin films bilayered with SnO 2 on Si (0 0 1) substrate, synthesized using pulsed laser deposition system. X-ray diffraction study reveals that both LBMO and SnO 2 show polycrystalline growth over the substrate. Atomic force microscopy shows interesting pyramidal structures of LBMO of size ∼2 μm × 1 μm × 0.1 μm. On the other hand, SnO 2 grows in the form of close packed cylindrical clusters of ∼200 nm radius. Near-field optical microscopy (NSOM) study using 532 nm laser reveal that optical NSOM output intensity in LBMO is four times less than SnO 2 signal. Transport characterizations show that this bilayer configuration exhibit non-linear current–voltage characteristics from 300 upto 50 K. The nature becomes linear below this temperature. The results project the system as a promising candidate in non-conventional device category in the area of spintronics.