Spin Transfer Switching Dynamics in Magnetic Nanostructures

Recent experimental evidence of spin transfer switching at reasonably low current densities of 10(7)similar to 10(9) A/cm(2) in magnetic nanostructures has triggered keen research interest in this area. We investigate the effect of current density J and spin polarization ratio P on the magnetization switching dynamics of an exemplary ferromagnetic nanostructure of dimensions 50 x 50 x 10 nm(3). The simulations are performed based on a three-dimensional micromagnetic model which incorporates the Slonczewski spin transfer torque and the damping effects of eddy current. Our simulation results show that, in general, a faster magnetic reversal speed can be achieved with a larger P and this dependence on P becomes more significant with an increase in J. Our numerical simulation indicates the optimal conditions in terms of the applied current properties J and P for fast spin transfer switching in the presence of eddy currents.