Skymions and Bimerons—A New Spin
Neuromorphic computing or neuromorphic engineering uses algorithms and electronic circuits to mimic our neuro-biological system. And it is gaining ground. Skyrmions and bimerons, fundamental topological spin textures in magnetic thin films, have asymmetric exchange interactions. Given their multiple degrees of freedom, they can carry information for next-gen low energy consumption memory, advanced neuromorphic computing, and advanced quantum computing.
The transformation between isolated skyrmions and bimerons will be essential for future computing architecture based on multiple topological bits. Effective ways are needed to realize the creation, transformation, and manipulation of skyrmions and bimerons in magnetic materials.
In a recent study published in Nano Letters, researchers at Shinshu University in Japan and their international collaborators demonstrated that the creation of isolated skyrmions and their subsequent transformation to bimerons are possible in a magnetic disk. Surrounded by a current-carrying and omega-shaped microcoil, the electric current-induced Oersted field and temperature-induced perpendicular magnetic anisotropy variation play essential roles in the transformation. Researchers found that:
- Current injected into the microcoil can generate an Oersted field to switch the magnetization of the magnetic disk in the out-of-plane directions
- Current injected into the microcoil can heat the magnetic disk and increase of device temperature
- A temperature-induced decrease of magnetic anisotropy is realized in the magnetic disk, leading to the magnetization reorientation from the out-of-plane direction to the in-plane direction and fostering the transformation
The results demonstrate the possibility that two different types of topological spin textures can be hosted by the same magnetic film with asymmetric exchange interactions, providing the ability to create novel spintronic applications based on different types of topological spin textures.