Broadband Ferromagnetic Resonance Study of ${\hbox{Co}}_{2}{\hbox{MnSi}}$ Thin Films: Effect of the Film Thickness

The thickness dependence of the static and dynamic properties of Co
₂
MnSi (CMS) full Heusler was investigated. Five samples with thickness ranging from 7 to 100 nm were deposited by rf magnetron sputtering on single crystal MgO(001). X-ray diffraction and transmission electron microscopy (TEM) evidence the epitaxial growth of samples, with an epitaxial relationship MgO(001)[100]//CMS(011)[110]. Magnetic properties were studied by standard magnetometry and broadband stripline ferromagnetic resonance (FMR). We observe a four-fold magnetocrystalline anisotropy K
_c
= 1.5 × 10
⁵
erg/cm
³
for thicker samples, and an increase of K
_c
up to 2.6 × 10
⁵
erg/cm
³
for the thinnest sample, accompanied by an increase of saturation magnetization. We attribute this behavior to interfacial effect (strain or stoichiometry).