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arXiv · 0907.2125

Effects of oxygen-reducing atmosphere annealing on LaMnO$_3$ epitaxial thin films

W S Choi·Z Marton·S Y Jang·S J Moon·B C Jeon·J H Shin·S S A Seo·T W Noh·K Myung-Whun·H N Lee·Y S Lee
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Abstract

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

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W S Choi, Z Marton, S Y Jang, S J Moon, B C Jeon, J H Shin, S S A Seo, T W Noh, K Myung-Whun, H N Lee, Y S Lee. 2009-07-13. Effects of oxygen-reducing atmosphere annealing on LaMnO$_3$ epitaxial thin films. https://doi.org/10.1088/0022-3727/42/16/165401

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