Giant in-plane anisotropy in manganite thin films driven by strain-engineered double exchange interaction and electronic phase separation

Abstract

We investigate epitaxial Pr0.65(Ca0.7Sr0.3)0.35MnO3 thin film grown on orthorhombic (110) NdGaO3 substrate which breaks the lattice symmetry and affects the phase separated ground state. As a result of the anisotropic substrate strain, giant in-plane magnetic and magnetotransport anisotropy are observed, which is related to the anisotropic coupling and competition between the double-exchange interaction and the Jahn-Teller distortion. Furthermore, the in-plane anisotropy shows a distinct enhancement near the metal-insulator transition, implying a significant contribution from the phase separation to the anisotropic transport behaviors.