Topologically-protected magnetic skyrmion for reducing dissipation beyond the limit

Coupled magnetic moment and Dirac electron assemblies have recently attracted attention on account of usage for high density data storage and quantum computation. A fundamental difficulty is in bringing such bits of information up to room temperature and stabilizing against other interactions. Here, we modeled multi-layer heterostructure combined with ferromagnet and topological insulator thin films where the robust room temperature topological spin texture (zero-field magnetic skyrmion) was simulated and shown to be controlled and protected by interfacial magnetism. The non-collinear alignment of the interfacial robust spin texture is a crucial ingredient for emerging high density memory and logic devices under zero net or discrete topological charge conditions via using skyrmioniums. Further, we numerically demonstrate the motion of concentric skyrmioniums in different material stacks at zero and room temperatures and compare their nucleation and current-driven motion characteristics. We found that the typical current densities for driving the concentric skyrmioniums on topological insulators is around 2-3 orders of magnitude smaller than those in typical Pt/Co bilayer systems. These results highlight the key role of interface band structure and carrier density.