Anisotropic stress relief mechanism in epitaxial La_(0.67)Sr_(0.3)MnO_3 films

摘要

We report an anisotropic misfit stress relief mechanism in thin La_(0.67)Sr_(0.3)MnO_3 (LSMO) films coherently grown on NdGaO_3(110) substrates. These results are uniquely related to the orthorhombicity of the LSMO. The x-ray diffraction measurements and quantitative simulations demonstrate that biaxial mismatch stress is relieved differently along in-plane directions perpendicular to each other: in the [110] direction stress is accommodated by decrease of the y angle of the orthorhombic LSMO unit cell, while in the [001] direction stress is partially relieved by periodic lattice modulations.