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arXiv · 2502.14357

Twinning in ferromagnetic Heusler Rh2MnSb epitaxial thin films

Artem Shamardin·Stanislav Cichoň·Esther de Prado·Jan Duchoň·Michal Rameš·Ladislav Fekete·Jaromír Kopeček·Šimon Šťastný·Aleš Melzer·Michal Hubert·Martin Veis·Ján Lančok·Oleg Heczko
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Abstract

Epitaxially grown full Heusler alloy of Rh2MnSb thin films were prepared for the first time using DC magnetron sputtering. The films were deposited on MgO [001] substrates with a deposition temperature of 600°C, 700°C, and 800°C. We report the structural, morphological, optical, magneto-optical, and magnetic properties of the films with a 200 nm nominal thickness. The grown-at-600°C film was close to stoichiometric and exhibited L21 ordering typical for Heusler alloys. The single-phase Rh2MnSb film had a tetragonal structure with lattice parameters close to the bulk material. X-ray photoelectron spectroscopy revealed the metallic character of the film free from contamination. The tetragonal films exhibited discernible regular twinning with the majority of twin domains with the c-axis perpendicular to the surface due to a substrate constraint. The twin formation was studied by atomic force and transmission electron microscopy and by X-ray diffraction. Magnetic measurements showed TC of about 220-275 K and saturation magnetization of about 55 emu/g, close to the bulk material. Magneto-optical Kerr effect measurements of the film prepared at 600 °C affirmed paramagnetic behavior at room temperature and suggested the half-metallic behavior. The observed properties highlight the potential for further investigations of Rh2MnSb's thin films, focusing on compositional and structural control.

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Artem Shamardin, Stanislav Cichoň, Esther de Prado, Jan Duchoň, Michal Rameš, Ladislav Fekete, Jaromír Kopeček, Šimon Šťastný, Aleš Melzer, Michal Hubert, Martin Veis, Ján Lančok, Oleg Heczko. 2025-02-20. Twinning in ferromagnetic Heusler Rh2MnSb epitaxial thin films. https://doi.org/10.1016/j.jallcom.2025.184143

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