Twinning in ferromagnetic Heusler Rh2MnSb epitaxial thin films

• DOI: 10.48550/arxiv.2502.14357
• Publication Date: 2025-01-01
• Authors: Shamardin, Artem; Cichoň, Stanislav; de Prado, Esther; Duchoň, Jan; Rameš, Michal; Fekete, Ladislav; Kopeček, Jaromír; Šťastný, Šimon; Melzer, Aleš; Hubert, Michal; Veis, Martin; Lančok, Ján; Heczko, Oleg
• Keywords: Condensed Matter - Materials Science; Materials Science (cond-mat.mtrl-sci); FOS: Physical sciences

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.<br/>17 pages, 11 figures<br/>