  In a bilayer consisting of an insulator (I) and a ferromagnetic metal (FM),
interfacial spin orbit scattering leads to spin mixing of the two conducting
channels of the FM, which results in an unconventional anisotropic
magnetoresistance (AMR). We theoretically investigate the magnetotransport in
such bilayer structures by solving the spinor Boltzmann transport equation with
generalized Fuchs-Sondheimer boundary condition that takes into account the
effect of spin orbit scattering at the interface. We find that the new AMR
exhibits a peculiar angular dependence which can serve as a genuine
experimental signature. We also determine the dependence of the AMR on film
thickness as well as spin polarization of the FM.
