Strain response of La0.7Sr0.3CoO3 epitaxial thin films probed by SrTiO3 crystalline microcantilevers

We investigate the effect of tensile strain on the resistivity of La 0.7 Sr 0.3 CoO 3 thin films grown on SrTiO 3 microcantilevers. Strain is applied by bending the microcantilevers both mechanically through an atomic force microscope tip and electrostatically. A strain gauge factor of 12 is observed, similar to the value measured for manganite thin films. Such low value evidences the role of extrinsic effects in the cobaltites giant gauge factor observed by other authors.