Determination of the strain dependence of resistance inLa0.7Sr0.3MnO3∕PMN−PTusing the converse piezoelectric effect

Abstract

We have deposited ${\mathrm{La}}_{0.7}{\mathrm{Sr}}_{0.3}\mathrm{Mn}{\mathrm{O}}_{3}$ (LSMO) thin films on piezoelectric $(1\ensuremath{-}x)\mathrm{Pb}({\mathrm{Mg}}_{1∕3}{\mathrm{Nb}}_{2∕3}){\mathrm{O}}_{3}\ensuremath{-}x\mathrm{Pb}\mathrm{Ti}{\mathrm{O}}_{3}$ $(x\ensuremath{\sim}0.3)$ (PMN-PT) single-crystal substrates and studied the effects of substrate-induced lattice strain on the resistance of the LSMO films. By applying electric fields across the PMN-PT substrate, we in situ induce an in-plane compressive (tensile) strain in the PMN-PT substrate via the converse piezoelectric effect. The induced strain is transferred to the LSMO film, which then imposes an in-plane compressive (tensile) strain on the LSMO film, thereby causing a linear decrease (increase) in the resistance of the LSMO film. Based on the experimental results, we establish quantitative relationships between the resistance of the LSMO film and the converse piezoelectric-effect-induced out-of-plane and in-plane strains in the PMN-PT substrate and LSMO film, respectively.