SSRL: Single Skyrmion Reconfigurable Logic Utilizing 2-D Magnus Force on Magnetic Racetracks

Abstract

Magnetic racetrack memory has frequently been complicated by the pinning of domain wall bits on the one hand and the need to engineer precise synchronization and inter-track repulsion between skyrmionic bits on the other. Such proposals, however, do not capitalize on the complex 2-D motion of skyrmions, such as transverse Magnus force that tends to deviate the skyrmion trajectory from rectilinear motion along the current drive. The transverse deviation associated with such a skyrmion Hall effect is normally considered a liability for skyrmions, and efforts have focused on eliminating rather than utilizing it for proposed device applications. We propose a simple single skyrmion-based circuit macro with elementary and higher-order logic gates that utilize Magnus force and propose reconfigurable logic built on these gates. We demonstrate the reliability of the proposed approach with micromagnetics simulation. The energy consumption in this circuit lies mainly in the overhead, with the racetrack consuming a small fraction. The energy–delay product (EDP) is correspondingly low and can be improved by boosting the skyrmion speed.

Keywords

• Domain walls
• magnetic tunnel junction (MTJ)
• racetrack
• reconfigurable logic
• skyrmions
• voltage-controlled magnetic anisotropy (VCMA)