A skyrmion-based non-volatile racetrack with a potential well structure

Abstract

In this paper, we present a new approach to reduce the volatility and chaos of the racetrack based on skyrmions. A multilayer (Pt/Co/Cu/Co) structure is designed, where energy potential wells are created in the upper Co layer because of the magnetostatic interaction between the upper Co layers and the Co rings at the bottom layer. The potential wells can store codes that are denoted by skyrmions or a ferromagnetic state. By periodically injecting out-of-plane and in-plane currents, the codes can be generated and controlled to pass through the potential wells one by one. All the codes can be stored in the potential well without loss and chaos, regardless of whether it is code ‘1’ that is denoted by a skyrmion or it is code ‘0’ that is denoted by a ferromagnetic state. The feasibility of this method is proved by micromagnetic simulations. Our design may provide an effective way to reduce signal volatility in skyrmion-based racetrack memory.

Nucleation and manipulation of skyrmions by spin currents mediated by an antiferromagnetic layer

“…The small size, topological protection, and ease of manipulation by current all make skyrmions attractive in memory devices [4][5][6][7][8]. Magnetic skyrmions exhibit novel dynamics and are of interest as carriers of binary digits or logic elements in future spintronic devices [9][10][11][12][13]. Research on how to generate stable skyrmions more efficiently has aroused great interest.…”