Magnetism, symmetry and spin transport in van der Waals layered systems

By Hidekazu Kurebayashi, Jose H. Garcia, Safe-Ur-Rahman Khan, J. Sinova, S. Roche. Nature Reviews Physics, 2021

179 citations recorded by the source corpus.

The discovery of an ever-increasing family of atomic layered magnetic materials, together with the already established vast catalogue of strong spin–orbit coupling and topological systems, calls for some guiding principles to tailor and optimize novel spin transport and optical properties at their interfaces. Here, we focus on the latest developments in both fields that have brought them closer together and make them ripe for future fruitful synergy. After outlining fundamentals on van der Waals magnetism and spin–orbit coupling effects, we discuss how their coexistence, manipulation and competition could ultimately establish new ways to engineer robust spin textures and drive the generation and dynamics of spin current and magnetization switching in 2D-materials-based van der Waals heterostructures. Grounding our analysis on existing experimental results and theoretical considerations, we draw a prospective analysis about how intertwined magnetism and spin–orbit torque phenomena combine at interfaces with well-defined symmetries and how this dictates the nature and figures of merit of spin–orbit torque and angular momentum transfer. This will serve as a guiding role in designing future non-volatile memory devices that utilize the unique properties of 2D materials with the spin degree of freedom. Spintronic properties of layered materials combining magnetism and strong spin–orbit coupling can be tailored by proper optimization of chemical interactions and structural material symmetries. This Review draws a route to achieving best performing material design for reaching the upper limit of spin–orbit torque efficiency in switching magnetization. Fabrication of 2D van der Waals magnetic systems offers unprecedented opportunities for controlling magnetism and spin transport phenomena down to the monolayer limit. Many van der Waals magnetic systems possess a low-symmetry crystalline structure, providing an array of exotic spin–orbit Hamiltonians, together with added richness arising from interface phenomena driven by layer-to-layer registry. Understanding the intertwined contribution of spin–spin interaction and interfacial symmetries is crucial for maximizing the full potential of their spin–orbit torque efficiency. This exciting research field of spin transport at the frontier of layered spin–orbit coupling and magnetism will lead to discoveries of new materials, novel transport effects, topological phenomena and unconventional electron correlation physics. Fabrication of 2D van der Waals magnetic systems offers unprecedented opportunities for controlling magnetism and spin transport phenomena down to the monolayer limit. Many van der Waals magnetic systems possess a low-symmetry crystalline structure, providing an array of exotic spin–orbit Hamiltonians, together with added richness arising from interface phenomena driven by layer-to-layer registry. Understanding the intertwined contribution of spin–spin interaction and interfacial symmetries is crucial for maximizing the full potential of their spin–orbit torque efficiency. This exciting research field of spin transport at the frontier of layered spin–orbit coupling and magnetism will lead to discoveries of new materials, novel transport effects, topological phenomena and unconventional electron correlation physics.

Subfields: Electrical and Electronic Engineering, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/9b7bb7e136a724324cad54a864a5cad4e80138fd