Unconventional Spin–Orbit Torques by 2D Multilayered MXenes for Future Nonvolatile Magnetic Memories

MXenes have attracted attention in recent years owing to their 2D layered structures with various functionalities. To open a new application field for MXenes in the realm of electronic devices, such as ultrahigh‐integrated magnetic memory, a spin–orbit torque (SOT) bilayer structure with MXene of Cr 2 N is developed: substrate//Cr 2 N/[Co/Pt] 3 /MgO using the magnetron sputtering technique. Field‐free current‐induced magnetization switching in the bilayer structure is demonstrated, regardless of the charge current directions with respect to the mirror symmetry lines of Cr 2 N crystal. This is a specific characteristic for the 2D MXene‐based SOT‐devices. As the SOT efficiency increases with increasing the Cr 2 N thickness, the first‐principles calculations predict an intrinsic orbital‐Hall conductivity with the dominant out‐of‐plane component, comparing to the spin‐Hall conductivity in the Cr 2 N. X‐ray magnetic circular dichroism reveals the out‐of‐plane uncompensated magnetic moment of Cr () in the Cr 2 N layer at the interface, induced by contact with the Co in the [Co/Pt] 3 ferromagnetic layer. Therefore, the intrinsic bulk orbital‐Hall effect in MXene and the interfacial contribution such as spin‐filtering‐like effect owing to are considered as possible major mechanisms for the unconventional out‐of‐plane SOT in the device, rather than a crystal symmetry and/or an interlayer exchange coupling.