Characteristics of signal propagation in magnetic quantum cellular automata circuits

Magnetic quantum cellular automata (MQCA) is a nano-scale computational paradigm that utilises magnetic dipolar interaction and coupling to propagate and process binary information. Characteristics of signal propagation in MQCA circuits with pipelined clocking signals are evaluated for the purposes of fast and reliable logic operation. These circuits are simulated via the Landau-Lifshitz-Gilbert equations and object-oriented micro-magnetic framework tool. It is found that signal propagations in the thin nanomagnet circuits are blocked significantly as the damping parameter is increased; however, their switching times decrease as the damping parameter increases. Switching speeds of MQCA structures are improved as the thickness and damping parameter are increased. The results also show that the majority logic gate performs a complete reliable operation for nanomagnet thicker than about 20-nm, whereas for interconnect wire, thickness ranging from only about 20 to 25-nm introduces a successful operation.