Skyrmion racetrack memory with random information update/deletion/insertion

Racetrack memory (RM) has demonstrated great potential as nonvolatile mass storage in future advanced computer architectures. Domain wall (DW)-based RM first proposed in 2008 by IBM, however, suffers from challenges, such as storage density, scalability, and energy consumption. Recently, magnetic skyrmions, topologically protected particle-like spin textures, have expected to replace DWs as new information carriers in the RM design, owing to their superiorities to DWs in terms of topological stability, smaller size, as well as lower driving current density. Extensive investigations have been performed in skyrmion-based RM (Sky-RM) to date. Furthermore, skyrmions exhibits some unique properties that are inaccessible to DWs, thus enabling Sky-RM to explore some new functions that may be inaccessible to DW-RM. In this paper, a novel Sky-RM, capable of random information update/deletion/insertion, is proposed by exploiting the particle-likebehaviors of skyrmions. Micromagnetic studies are performed to validate the function and performance of these novel data operations, which may bring performance benefits in data access operations and enable new applications.