THE LONGITUDINAL AND TRANSVERSE MAGNETORESISTIVITIES AND THE AC SUSCEPTIBILITY OF FE10PT90

A summary of detailed measurements of field and temperature dependent magnetic and transport properties in Fe10Pt90 is presented, with parti cular emphasis on attempting to evaluate the influence of spin-orbit c oupling. Analysis of the field dependent AC susceptibility near the Cu rie temperature T(C) congruent-to 170 K enables effective exponent val ues to be estimated, although the presence of magnetic anisotropy aris ing from spin-orbit coupling prevents asymptotic exponent values from being found. The anisotropy of the magnetoresistance in this system al so originates from spin-orbit coupling, and this behaviour is discusse d in terms of both itinerant and localized models. A number of estimat es for T(C) are deduced from these different measurements and compared .