Skyrmionic states induced by local Dzyaloshinskii-Moriya interaction

Magnetic skyrmions, typically stabilized by the Dzyaloshinskii-Moriya interaction (DMI), are promising candidates as the information carriers for advanced spintronic applications. In conventional micromagnetic theory, formation and morphology of skyrmion are generally thought to be restricted by symmetries associated with specific point groups. Here, through symmetry analysis and first-principles-based spin Hamiltonian calculations, we demonstrate that even in systems with zero net DMI, local DMI contributions can result in energy gains that stabilize noncollinear skyrmionic states. Symmetry constraints on global DMI, for example, confirm that systems with D3h and D3d point group symmetries yield zero net DMI. We identify two two-dimensional magnets, Mn2AgTe4 and In2Cr2Te5, with D3h and D3d symmetries, respectively, where magnetic atoms exhibit 3m. site symmetry with their nearest neighbors. In these systems, local DMI stabilizes N & eacute;el-type skyrmions, forming a skyrmionic phase in Mn2AgTe4 and a metastable excitation state in In2Cr2Te5. This study expands the search for skyrmionic phases in materials with unconventional point group symmetries, enriching the landscape of skyrmionic systems.