Ab initio giant magnetoresistance and current-induced torques in Cr/Au/Cr multilayers

We report on an ab initio study of giant magnetoresistance (GMR) and current-induced torques (CITs) in Cr/Au/Cr trilayers that is based on nonequilibrium Green's functions and spin-density functional theory. We find substantial GMR due primarily to a spin-dependent resonance centered at the Cr/Au interface and predict that the CITs are strong enough to switch the antiferromagnetic order parameter at current densities similar to 100 times smaller than switching current densities in ferromagnetic metal circuits.