Magnetic anisotropy peculiarities of high-temperature ferromagnetic Mn_xSi_1−x (x ≈ 0.5) alloy films

¹ P.L. Kapitza Institute for Physical Problems RAS - Kosygina St. 2, 119334 Moscow, Russia
² National Research Centre “Kurchatov Institute” - Kurchatov Sq. 1, 123182 Moscow, Russia
³ Kotel'nikov Institute of Radio Engineering and Electronics RAS - 141190 Fryazino, Moscow region, Russia
⁴ Institute on Laser and Information Technologies RAS - Svyatoozerskaya St. 1, 140700 Shatura, Moscow region, Russia
⁵ Prokhorov General Physics Institute RAS - Vavilov St. 38, 119991 Moscow, Russia
⁶ Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research Bautzner Landstrasse 400, 01328 Dresden, Germany

^(a) drovosekov@kapitza.ras.ru

Received: 15 April 2016
Accepted: 19 August 2016

Abstract

Thin films of Mn_xSi_1−x alloys with different Mn concentration grown by the pulsed-laser deposition (PLD) method onto the Al₂O₃ (0001) substrate were investigated in the temperature range 4–300 K using ferromagnetic resonance (FMR) measurements in the wide range of frequencies and magnetic fields . For samples with , FMR data show clear evidence of ferromagnetism (FM) with high Curie temperatures . These samples demonstrate the complex and unusual character of magnetic anisotropy described in the frame of phenomenological model as a combination of the essential second-order easy-plane anisotropy contribution and the additional fourth-order anisotropy contribution with the easy direction normal to the film plane. We explain the obtained results by a polycrystalline (mosaic) structure of the films caused by the film-substrate lattice mismatch.