Interlayer exchange coupling (IEC) behavior in epitaxial Co2 MnSi (20 nm)/Cr/Fe (7 nm) trilayers has been investigated against Cr spacer thickness (tcr = 0.3-6.3 nm). High-quality trilayer samples have grown on a Cr (5 nm)/Au (30 nm)/Cr (15 nm) buffer layer on a MgO substrate by ultrahigh vacuum (UHV) compatible dc sputtering method. A simple numerical simulation model has been used to explain magnetization process, which shows good agreement with the experimental M - H curves. The values of bilinear and biquadratic coupling energy (J1 and J2) and the cubic anisotropy energy of Co2MnSi and Fe (Kcms and K Fe) have been determined uniquely from the simulations. As a result, we have found a dominating contribution of biquadratic (90°) coupling and absence of bilinear (180°) coupling in all the samples with nonferromagnetic coupling. It has also been found that, the energetical competition between 90° coupling energy and anisotropy energy largely affects the magnetization process due to different easy directions of bottom Co2 MnSi (110) and Fe (100).
- Biquadratic coupling
- Heusler alloys
- Interlayer exchange coupling
- Spin polarization
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering