Magnetotransport: An ideal probe of anisotropy energies in epitaxial films (invited)

Magnetotransport measurements provide an ideal probe to determine the various anisotropy energies in epitaxial magnetic films. The extraordinary Hall effect (EHE) can be used to determine the perpendicular or surface anisotropy energy while the anisotropic magnetoresistance (AMR) can be used to investigate the in-plane anisotropy energies. The advantage of magnetotransport over more tranditional measurement techniques used to determine these anisotropy energies is the ease of the technique, the lack of a need for sophisticated equipment, and the insensitivity of the techniques to the magnetic properties of a semiconducting or insulating substrate. Both the EHE and the AMR have been used to study the magnetic properties of epitaxial iron films grown on GaAs substrates. The results of the EHE and the AMR study and how the various anisotropy energies compare with those determined by the more traditional techniques of ferromagnetic resonance and vibrating sample magnetometry will be discussed.