Oriented domains in a thin film of La₀.₈Sr₀.₂MnO₃ prepared by laser molecular-beam epitaxy

Abstract

A thin film of La_{0 8}Sr_0.2MnO₃, prepared by computer-controlled laser molecular-beam epitaxy, on a single-crystal SrTiO₃ substrate, has been characterized by transmission electron microscopy. Electron microdiffraction and high-resolution imaging reveal that the as-received thin film with a thickness of 200 nm is epitaxially grown on the SrTiO₃(001) substrate. The microstructures in the whole film are clarified in terms of the oriented microdomains. The crystallographic relationships of these domains are discussed on the basis of an orthorhombic unit cell. Theoretical calculations based on a geometrical model that was recently proposed and applied to a number of epitaxial systems have been carried out to rationalize the present observations.