Search results for "Racetrack memory"
showing 4 items of 4 documents
Staggered magnetic nanowire devices for effective domain-wall pinning in racetrack memory
2019
Domain-wall memory devices, in which the information is stored in nanowires, are expected to replace hard disk drives. A problem that remains to be solved in domain-wall memory is to pin the domain walls in a controllable manner at the nanometer scale using simple fabrication. We demonstrate the possibility to stabilize domain walls by making staggered nanowires. Controllable domain-wall movement is exhibited in permalloy nanowires using magnetic fields where the pinning field is about 10 mT. The pinning field and stability of the domain walls can be increased by adjusting the offset dimensions of the staggered nanowires. Domain-wall velocities of about 200 m/s are computed for the experime…
Magnetic skyrmions: from fundamental to applications
2016
In this topical review, we will discuss recent advances in the field of skyrmionics (fundamental and applied aspects) mainly focusing on skyrmions that can be realized in thin film structures where an ultrathin ferromagnetic layer (<1 nm) is coupled to materials with large spin-orbit coupling. We review the basic topological nature of the skyrmion spin structure that can entail a stabilization due to the chiral exchange interaction present in many multilayer systems with structural inversion asymmetry. The static spin structures and the dynamics of the skyrmions are also discussed. In particular, we show that skyrmions can be displaced with high reliability and efficiency as needed for t…
Chiral Magnetic Domain Wall and Skyrmion Memory Devices
2021
In the chapter, we have reviewed the fundamental physics for designing magnetic domain wall memories, especially domain wall racetrack memories. An overview of how the racetrack has been functionally improved and the fundamental physics behind the operating mechanism has developed is shown. Material wise, the design of the racetrack has changed from using in-plane magnetic materials to out-of-plane magnetic materials. The process of changing the material design resulted in new physics such as the spin-orbit torques (SOTs) and the Dzyaloshinskii-Moriya interaction (DMI) which resulted in domain wall motion with higher efficiency and stability. The SOT is the main mechanism in moving the doma…
Magnetic domain-wall racetrack memory for high density and fast data storage
2012
The racetrack memory device is a new concept of Magnetic RAM (MRAM) based on controlling domain wall (DW) motion in ferromagnetic nanowires. It promises ultra-high storage density thanks to the possibility to store multiple narrow DWS per memory cell. By using read and write heads based on magnetic tunnel junctions (MTJ) with perpendicular magnetic anisotropy (PMA) fast data access speed can also be achieved. Thereby the racetrack memory can be used as universal storage to address both embedded and standalone applications. In this paper, we present the device physics, integration circuit and architecture designs of a racetrack memory based on MTJs with PMA. Mixed SPICE simulations at 65 nm …