Strain Effect in La_1-xCa_xMnO₃ Thin Films

Abstract

The lattice parameter, transport properties, and magnetoresistance effect of perovskite manganite La_0.7Ca_0.3MnO₃thin films deposited on several substrates (SrTiO₃(001), LaSrGaO₄(001), YAlO₃(001), LaA1O₃ (001)) have been investigated in the range of themismatchof -4∼1% between the film and the substrates. We have found that metal-insulator transition temperature (T_c^ρ)depend on the out-of-plane lattice parameter (c). Magnetoresistance effect increases linearly with decreasing T_c^ρ. These results are understood in terms of the latticeeffect induced by the strain.