Nanomagnetic logic: Investigations on field-coupled computing devices by experiment-based compact modeling

A compact model for the design of nanomagnetic logic based on experiments with field-coupled nanomagnets is presented. Two different types of dots for signal propagation in a wire and logic operations in a majority gate are introduced. The switching behavior and the interaction of fabricated nanomagnets is analyzed by MOKE measurements. Partial irradiation with a focused ion beam (FIB) is used to influence the switching and the interaction of the utilized nanomagnets. Experimental results are used to calibrate the nanomagnetic compact models. Investigations on nanomagnetic wires and an XOR gate are performed. Simulations show that the error rate mainly depends on the switching field variations from dot to dot and the strength of the coupling field between the dots. High coupling fields by small gaps between the nanomagnets and accurate control of switching field variations by partial FIB irradiation turn out to be the key for realizing reliable NML systems.