Skyrmionic majority and minority gates for arithmetic and logic units

Skyrmions display significant possibilities for applications in beyond-CMOS technology owing to their prominent features, such as nanoscale size, high mobility, and excellent stability because of the topologically protected structure. This work presents skyrmion-based majority gate and minority gate architectures implemented on a ferromagnet-heavy metal bilayer structure. These skyrmions move along ion-defined tracks. The energy-efficient and compact logic gates are implemented by utilizing the skyrmion-skyrmion repulsion property, ion-defined tracks and their edge confinement effects. The proposed designs are validated through micromagnetic simulations, which show their ability to execute the basic logic functions such as NOT, AND, OR, NAND, and NOR without additional physical modifications or voltage-to-skyrmion conversion circuitry. Systematic variations in the track inclination angle (φ) and lateral track spacing (YLat) indicate that successful gate operation is restricted to angles below10∘, beyond which skyrmion trajectories deviate.YLatshould not be excessively wide; otherwise, skyrmions will be insufficiently close to each other to exert a repulsion force, thus hindering their ability to cross the barriers. The temperature fluctuation study shows the susceptibility of these devices up toTnoise=60Kfor increased barrier widths, anisotropy gradient, and applied current. Furthermore, a cascadable full adder is designed using the proposed majority and minority gates, demonstrating the potential for scalable and low-power beyond-CMOS nonvolatile logic-in-memory architectures. The proposed skyrmion-based majority and minority gates are structurally simpler, cascadable, and fully conservative.