Designing Layered 2D Skyrmion Lattices in Moiré Magnetic Heterostructures

Abstract

AbstractSkyrmions are promising for the next generation of spintronic and magnonic devices, but their zero‐field stability and controlled nucleation through chiral interactions remain challenging. In this theoretical study, the potential of moiré magnetic heterostructures to generate ordered skyrmion lattices from the stacking‐dependent magnetism in 2D magnets is explored. Heterostructures formed by twisting ultrathin CrBr3 films on top of CrI3 substrates are considered, assuming a moderate interfacial Dzyaloshinskii–Moriya interaction. At large moiré periodicity and appropriate substrate thickness, a moiré skyrmion lattice emerges in the interfacial CrBr3 layer due to the weaker exchange interactions in CrBr3 compared to CrI3. This lattice is then projected to the remaining layers of the CrBr3 film via chiral interlayer exchange fields. By varying the pristine stacking configurations within the ultrathin CrBr3 film, layered ferromagnetic and antiferromagnetic skyrmion lattices without the need for a permanent magnetic field are realized. These findings suggest the possibility of creating ordered skyrmion lattices in moiré magnetic heterostructures, enabling further exploration of their fundamental properties and technological relevance.