Strain-dependent surface evolution and magneto-transport properties of La 0.7Sr 0.3MnO 3 epilayers on SrTiO 3 substrates

Abstract

This study investigated how lattice strain affects the surface morphology of La 0.7Sr 0.3MnO 3 (LSMO) epilayers on SrTiO 3 (STO) substrates by X-ray scattering and atomic force microscopy (AFM). Almost pseudomorphic growth of LSMO epilayers is observed up to a thickness of 300 Å on an STO substrate. The Jahn-Teller strain in the LSMO lattice increases as the epilayer thickness falls. The dynamic roughness exponent of the rapid roughening regime associated with the strain relief is ∼1.029. Variations in magnetic and transport properties of LSMO epilayers are discussed with reference to changes in the lattice strain in the LSMO epilayers.