Electron-magnon diffusion and magnetization reversal detection in FePt thin films
A. P. Mihai, J. P. Attan\'{e}, A. Marty, P. Warin, and Y. Samson

We measured the dependence of the electrical resistivity with perpendicular magnetic field in FePt (10-32 nm) / MgO layers - from 3 to 300 K. We show that the magnetoresistance is proportional to both the perpendicular magnetization of the FePt layer and the perpendicular applied field. Building on previous models, we show that this magnetoresistance can be ascribed to electron-magnon interactions, giving a linear dependence of resistivity upon magnetization in the limit of a low field/magnetocristalline anisotropy ratio. This magnetoresistance effect can be used to follow magnetization reversal in certain conditions, with perspectives that we discuss with respect to other magnetoresistive effects.

© 2008 The American Physical Society.