A comparison of ferromagnetic resonance and magneto optical Kerr effect on thin Fe films on InAs(001)

A combination of STM, SQUID magnetometry, FMR and MOKE is used to study the structural and magnetic properties of thin iron films grown on InAs(001) (4×2)/c(8×2). The different magnetic characterization methods of this paper allow measurements of the magnetic anisotropies in the saturated and non-saturated state. Here we show results of a SQUID/FMR investigation on a 12 monolayer thick Fe film. As expected, FMR measurements find a four-fold symmetry of the magneto crystalline anisotropy, but with an additional uniaxial contribution. The dependence of the remanence on the magnetization angle computed from the magnetic parameters obtained in the saturated state is compared to experimental remanence data measured using MOKE. Good agreement is found. The InAs-substrate quality prior to growth, the nucleation behavior and the thickness-dependent granular structure of the Fe-layer are studied with STM. The origin of the magnetic anisotropies is discussed in terms of these structural data.