from first-principles-based effective Hamitonian*

Topological magnetic states, such as skyrmions, experience rapid recent development due to their potential application in advanced spintronics. Such topics become even more intriguing and promising, considering the recent progresses in 2D magnets, such as Fe₃GeTe₂ with near room-temperature Curie temperature. However, despite quite a few studies on Fe₃GeTe₂, it still lacks a reliable model to describe the skyrmionics in Fe₃GeTe₂, especially the elusive Néel-type vs Bloch-type. Here we perform theoretical studies and report our newly developed first-principles-based effective Hamiltonian, which not only reproduces the complex topological states in Fe₃GeTe₂, but also sheds light on the elusive topics.