Work

Interplay of magnetocrystalline and magnetoelastic anisotropy in epitaxial Co ( 10 1 ¯ 0 ) films

Year: 2025

Type: article

Abstract: With the goal of creating an in-plane (IP) uniaxial anisotropy system, we deposited a thickness series of epitaxial Co ( 10 1 ¯ 0 ) films grown on Si(110) substrates with Ag(110) and Cr(211) buffer layers by magnetron sputtering. However, quantifying the IP magnetic anisotropy using ferromagnetic resonance measurements revealed a much more complex behavior than expected for a simple uniaxial system like hexagonally close-packed (hcp) Co. To understand the experimental results, an in-depth x-ray diffraction analysis of the film structure was performed. Even at a thickness of 100 nm, it revealed an anisotropic strain in the Co films, mainly within the Co basal plane, while the c axis remained mostly unaffected. Calculations show that such unrelaxed strain induces a significant magnetoelastic anisotropy, which counteracts the magnetocrystalline one and, as a result, reduces the overall effective anisotropy. A detailed analysis revealed that mainly the compressive strain along the Co [ 10 1 ¯ 0 ] out-of-plane direction is responsible for the observed magnetoelastic anisotropy, while the tensile strain along the Co [ 1 ¯ 2 1 ¯ 0 ] IP direction only plays a minor role.

Source: Physical review. B./Physical review. B

DOI: 10.1103/physrevb.111.054431