  We present here a self consistent solution of quantum transport, using the
Non Equilibrium Green's Function (NEGF) method, and magnetization dynamics,
using the Landau-Lifshitz-Gilbert (LLG) formulation. We have applied this model
to study current induced magnetic switching due to `spin torque' in a device
where the electronic transport is ballistic and the free magnetic layer is
sandwiched between two anti-parallel ferromagnetic contacts. The device shows
clear hysteretic current-voltage characteristics, at room temperature, with a
sharp transition between the bistable states and hence can be used as a
non-volatile memory. We show that the proposed design may allow reducing the
switching current by an order of magnitude.
