Magnetoelastic coupling induced magnetic anisotropy in Co2(Fe/Mn)Si thin films

Abstract

We report the influence of in-plane strain on uniaxial magnetic anisotropy of Co2(Fe/Mn)Si [CF(M)S] films grown on SrTiO3 (STO) and MgO by varying film thickness. The analysis of magnetic free energy functional for the films on STO showed the presence of magnetoelastic anisotropy with magnetostriction constant of 12.22 × 10−6 for CFS and 2.02 × 10−6 for CMS in addition to intrinsic magnetocrystalline anisotropy. Single-domain phase diagram reveals a gradual transition from in-plane to canted state with decreasing film thickness due to strain-induced tetragonal distortion. A maximum canting angle of 41.5° with respect to film plane is predicted for CFS (12 nm)/STO film. The authors thank M. Shivakumar for his help in magnetization measurements. H.P. and P.K.R. acknowledge financial support from Indian Institute of Technology Kanpur and Council for Scientific and Industrial Research (CSIR), Government of India. This work is partly supported by CSIR, New Delhi [Grant No. 80(0080)/12/EMR-II]. R.C.B. acknowledges J. C. Bose Fellowship of the Department of Science and Technology, Government of India.