Effects of oxygen-reducing atmosphere annealing on LaMnO₃epitaxial thin films

Abstract

We investigated the effects of annealing on LaMnO$_3$ epitaxial thin films\ngrown by pulsed laser deposition and propose an efficient method of\ncharacterizing their stoichiometry. Structural, magnetic, and optical\nproperties coherently indicate non-stoichiometric ferromagnetic and\nsemiconducting phases for as-grown LaMnO$_3$ films. By annealing in an\noxygen-reducing atmosphere, we recovered the antiferromagnetic and insulating\nphases of bulk-like stoichiometric LaMnO$_3$. We show that non-destructive\noptical spectroscopy at room temperature is one of the most convenient tools\nfor identifying the phases of LaMnO$_3$ films. Our results serve as a\nprerequisite in studying LaMnO$_3$ based heterostructures grown by pulsed laser\ndeposition.\n