Magnetic and Electronic Properties of Weyl Semimetal Co<sub>2</sub>MnGa Thin Films

oleh: Peter Swekis, Aleksandr S. Sukhanov, Yi-Cheng Chen, Andrei Gloskovskii, Gerhard H. Fecher, Ioannis Panagiotopoulos, Jörg Sichelschmidt, Victor Ukleev, Anton Devishvili, Alexei Vorobiev, Dmytro S. Inosov, Sebastian T. B. Goennenwein, Claudia Felser, Anastasios Markou

Format: Article
Diterbitkan: MDPI AG 2021-01-01

Deskripsi

Magnetic Weyl semimetals are newly discovered quantum materials with the potential for use in spintronic applications. Of particular interest is the cubic Heusler compound Co<sub>2</sub>MnGa due to its inherent magnetic and topological properties. This work presents the structural, magnetic and electronic properties of magnetron co-sputtered Co<sub>2</sub>MnGa thin films, with thicknesses ranging from 10 to 80 nm. Polarized neutron reflectometry confirmed a uniform magnetization through the films. Hard x-ray photoelectron spectroscopy revealed a high degree of spin polarization and localized (itinerant) character of the Mn <i>d</i> (Co <i>d</i>) valence electrons and accompanying magnetic moments. Further, broadband and field orientation-dependent ferromagnetic resonance measurements indicated a relation between the thickness-dependent structural and magnetic properties. The increase of the tensile strain-induced tetragonal distortion in the thinner films was reflected in an increase of the cubic anisotropy term and a decrease of the perpendicular uniaxial term. The lattice distortion led to a reduction of the Gilbert damping parameter and the thickness-dependent film quality affected the inhomogeneous linewidth broadening. These experimental findings will enrich the understanding of the electronic and magnetic properties of magnetic Weyl semimetal thin films.