Spin-Orbit Torques Using 2D Materials

Marcos H. D. Guimarães, University of Groningen

July 7, 2020

The manipulation of magnetization using materials with large spin-orbit coupling is very promising for applications in magnetic memory devices. In these devices, a charge current can be used to apply torques on the magnetization of an adjacent ferromagnet. In addition to their use in future nonvolatile data processing and storage devices, the study of these spin-orbit torques can unveil many of the material’s spintronic properties.

The large family of layered two-dimensional materials has shown to be an excellent candidate for the generation of spin-orbit torques. They provide large atomically-flat single crystals with various properties and very pristine interfaces which leads to an efficient transfer of spins from the layered material to the ferromagnet.

In this talk I will show how the crystal structure and material properties of these layered crystals can dictate the magnitude, direction, and symmetries of spin-orbit torques. In particular, I will show how the crystal structure can lead to torque symmetries which are forbidden in conventional devices. I will also discuss recent results on the layered insulating antiferromagnet NiPS3, where we observe large interfacial torques, with torque efficiencies comparable to best devices based on heavy metals.