Control of structure and spin texture in the van der Waals layered magnet CrSBr

Van der Waals magnetic materials are composed of atomically thin magnetically ordered layers stacked together. Here, aiming to control magnetism locally, Klein et al use an electron beam to create small regions where van der Waals layers are orientated perpendicular to the rest of the sample. Controlling magnetism at nanometer length scales is essential for realizing high-performance spintronic, magneto-electric and topological devices and creating on-demand spin Hamiltonians probing fundamental concepts in physics. Van der Waals (vdW)-bonded layered magnets offer exceptional opportunities for such spin texture engineering. Here, we demonstrate nanoscale structural control in the layered magnet CrSBr with the potential to create spin patterns without the environmental sensitivity that has hindered such manipulations in other vdW magnets. We drive a local phase transformation using an electron beam that moves atoms and exchanges bond directions, effectively creating regions that have vertical vdW layers embedded within the initial horizontally vdW bonded exfoliated flakes. We calculate that the newly formed two-dimensional structure is ferromagnetically ordered in-plane with an energy gap in the visible spectrum, and weak antiferromagnetism between the planes, suggesting possibilities for creating spin textures and quantum magnetic phases.

Automated summary

Van der Waals magnetic materials consist of atomically thin magnetically ordered layers. In this study, the researchers demonstrate nanoscale structural control in the layered magnet CrSBr by using an electron beam, which could lead to the creation of spin textures and quantum magnetic phases.