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arXiv · 1205.3475

GaMnN epitaxial films with high magnetization

Gerd Kunert·Sylwia Dobkowska·Tian Li·Helfried Reuther·Carsten Kruse·Stephan Figge·Rafal Jakiela·Alberta Bonanni·Jörg Grenzer·Wiktor Stefanowicz·Maciej Sawicki·Tomasz Dietl·Detlef Hommel
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Abstract

We report on the fabrication of pseudomorphic wurtzite GaMnN grown on GaN with Mn concentrations up to 10% using molecular beam epitaxy. According to Rutherford backscattering the Mn ions are mainly at the Ga-substitutional positions, and they are homogeneously distributed according to depth-resolved Auger-electron spectroscopy and secondary-ion mass-spectroscopy measurements. A random Mn distribution is indicated by transmission electron microscopy, no Mn-rich clusters are present for optimized growth conditions. A linear increase of the c-lattice parameter with increasing Mn concentration is found using x-ray diffraction. The ferromagnetic behavior is confirmed by superconducting quantum-interference measurements showing saturation magnetizations of up to 150 emu/cm^3.

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Gerd Kunert, Sylwia Dobkowska, Tian Li, Helfried Reuther, Carsten Kruse, Stephan Figge, Rafal Jakiela, Alberta Bonanni, Jörg Grenzer, Wiktor Stefanowicz, Maciej Sawicki, Tomasz Dietl, Detlef Hommel. 2012-05-17. GaMnN epitaxial films with high magnetization. https://doi.org/10.1063/1.4734761

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