Thermal processing effects on ultra-thin ferromagnetic Fe layers grown on GaAs(001)

We used Brillouin light scattering and magneto-optical Kerr effect measurements to study the magnetic properties of ultra-thin 1.5 nm Fe layers undergoing various annealing and high temperature growth processes on GaAs(0 0 1). We found that the thermal processing has a profound effect on the form and magnitude of the magnetic anisotropy and value of the coercivity. In addition, in situ scanning tunneling microscopy revealed that high temperature post-deposition annealing results in the formation of rectangular pits, while high temperature growth results in a rough faceted microstructure.