Modeling approach helps describe next-generation memory technologies

To develop memory devices with lower power, higher density, and faster speed than current technologies, corporate giants like IBM have invested in new strategies, such as memory devices that use walls induced by electrical current to separate magnetic domains in magnetic materials. However, the physics of current-driven domain-walls on recently discovered 2D magnetic materials is poorly understood. Abdul-Wahab et al. developed a multiscale modeling approach to accurately describe domain-wall dynamics in atomically thin compounds.

The authors predicted domain wall speeds at ultrafast rates (about 1,200 meters per second), which are very competitive relative to other compounds currently in use. The team also observed a hydrodynamic spin-liquid regime that could transmit information for large distances (over 10 micrometers), allowing practical device implementations.

“Our predictions create a pathway for the exploration of domain-wall technologies based on 2D magnetic materials and provide key details for their experimental realization,” said Elton Santos, who led the study. “Moreover, the new spin-hydrodynamic state puts 2D magnetic compounds inside of a new field of spintronics called magnonics. That is, the transmission of information using spin waves or magnons. Our work in this context opened several possibilities for further investigations.”

The model used multiscale methods involving ab initio and atomistic approaches to describe the domain walls driven by electrical currents and magnetic fields. The study also provided practical guidelines in terms of parameters used in lab fabrication of 2D-material-based magnets, such as substrates, conductivity, doping, etc.

“Striking possibilities are on the horizon, from the inclusion of 2D magnets into racetrack platforms, up to the fundamental aspects of the turbulent spin state observed in monolayer materials,” Santos said.

Source: “Domain wall dynamics in two-dimensional van der Waals Ferromagnets,” by Dina Abdul-Wahab, Ezio Iacocca, Richard F. L. Evans, Amilcar Bedoya-Pinto, Stuart Parkin, Kostya S. Novoselov, and Elton J.G. Santos, Applied Physics Reviews (2021). The article can be accessed at https://doi.org/10.1063/5.0062541 .

This paper is part of the Quantum Materials and 2D superlattices Collection, learn more here .