Edge-Mode Resonance-Assisted Switching of Nanomagnet Logic Elements

We study the ferromagnetic resonance (FMR) modes of arrays consisting of elements of supermalloy-based nanomagnet logic devices: individual rectangular magnets, lengthwise-coupled magnet pairs, and driver-input magnet pairs. In FMR experiments, we observe a center resonance mode for all three samples. Furthermore, edge modes can be resolved for arrays with individual rectangular magnets and lengthwise-coupled magnet pairs. By micromagnetic simulations, the characteristics of the experimentally observed precession modes are elaborated, and distinct edge modes not visible in the experiments are revealed. Based on these numerical investigations, we propose a new addressing scheme to switch a specific element of the driver-input magnet pair based on resonant excitation of the unique edge-mode resonance of the element. This new switching scheme could significantly reduce switching power and increase bit selectivity, and hence programming reliability.