Nanomagnetic circuits with spin torque majority gates

Nanomagnetic or spintronic circuits hold the promise of non-volatile and reconfigurable logic with small switching energy. The concept of circuits based on spin transfer torque switching in magnetic tunnel junctions is presented. Majority gates are concatenated without conversion to electric signals. A full adder circuit is simulated with a micromagnetic solver, dynamics of magnetization is explained via motion of domain walls. The switching speed and energy of the adder bit is comparable to single gates or nanomagnetic memories. A nonlinear transfer characteristic ensures noise margin.