Performance of synthetic antiferromagnetic racetrack memory: domain wall versus skyrmion. (18th July 2017)

• Record Type: Journal Article
• Authors: Tomasello, R; Puliafito, V; Martinez, E; Manchon, A; Ricci, M; Carpentieri, M; Finocchio, G
• Is Part Of: Journal of physics. Volume 50:Number 32(2017)
• Publication Date: 2017-07-18
• Subjects: micromagnetism -- spintronics -- racetrack memory -- domain wall -- skyrmion -- Dzyaloshinskii–Moriya interaction -- spin-Hall effect; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/aa7a98
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: A storage scheme based on racetrack memory, where the information can be coded in a domain or a skyrmion, seems to be an alternative to conventional hard disk drive for high density storage. Here, we perform a full micromagnetic study of the performance of synthetic antiferromagnetic (SAF) racetrack memory in terms of velocity and sensitivity to defects by using experimental parameters. We find that, to stabilize a SAF skyrmion, the Dzyaloshinskii–Moriya interaction in the top and the bottom ferromagnet should have an opposite sign. The velocity of SAF skyrmions and SAF Néel domain walls are of the same order and can reach values larger than 1200 m s −1 if a spin–orbit torque from the spin-Hall effect with opposite sign is applied to both ferromagnets. The presence of disordered anisotropy in the form of randomly distributed grains introduces a threshold current for both SAF skyrmions and SAF domain walls motions.