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arXiv · 2007.11982

Magnetic characteristics of epitaxial NiO films studied by Raman spectroscopy

J. Feldl·M. Budde·C. Tschammer·O. Bierwagen·M. Ramsteiner
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Abstract

Raman spectroscopy is utilized to study the magnetic characteristics of heteroepitaxial NiO thin films grown by plasma-assisted molecular beam epitaxy on MgO(100) substrates. For the determination of the N\'eel temperature, we demonstrate a reliable approach by analyzing the temperature dependence of the Raman peak originating from second-order scattering by magnons. The antiferromagnetic coupling strength is found to be strongly influenced by the growth conditions. The low-temperature magnon frequency and the N\'eel temperature are demonstrated to depend on the biaxial lattice strain and the degree of structural disorder which is dominated by point defects.

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J. Feldl, M. Budde, C. Tschammer, O. Bierwagen, M. Ramsteiner. 2020-07-23. Magnetic characteristics of epitaxial NiO films studied by Raman spectroscopy. https://doi.org/10.1063/5.0006085

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