Calculation of spin-dependent interface resistance

A simple expression for the interface resistance between two materials has been derived by Schep et al. [J. Magn. Magn. Mater. 177, 1166 (1998)] in terms of the transmission probability for electrons at the interface. This approximation is tested for a simple model interface and good agreement is found with solutions of the Boltzmann equation. Previously calculated values of the transmission probability rue used with this simple expression to evaluate the spin-dependent interface resistances of a number of ferromagnetic-normal metal interfaces. The agreement between the calculated results and the results extracted from experiments on Cu/Co argue that the interface resistance may not be dominated by defect scattering as is often assumed.