Temperature and angular dependence of the anisotropic magnetoresistance inepitaxial Fe films - art. no. 134432

We perform detailed temperature dependent measurements of the magnetoresist ance (MR) and its angular dependence of epitaxial Fe (110) films. The angul ar dependence of the MR at H = 10 kOe is found to change strongly when goin g from T = 4.2 K to T = 230 K. We analyze the data on the basis of Doring's equation. Second- and fourth-order angular dependent terms are found to be of equal importance, indicating strong deviations of the MR from a simple cos(2) phi dependence. One of the MR components is the ordinary or Lorentz magnetoresistance, which is strong at low temperatures and becomes smaller at higher temperatures, due to the reduction of the mean free path. By subt racting the ordinary magnetoresistance from the MR data we obtain the aniso tropic magnetoresistance. We decompose the temperature dependent anisotropi c magnetoresistance in the temperature dependent k constants of Doring's eq uation. These constants show a reduction between T = 20 K and T = 100 K, wh ich reflects the observed decrease of the anisotropic magnetoresistance. We present arguments that the temperature dependence of the anisotropic magne toresistance is most likely due to the change from defect-dominated scatter ing to phonon-dominated scattering, each of which has its own anisotropic m agnetoresistance.