Neutron spectroscopy evidence on the dual nature of magnetic excitations in a van der Waals metallic ferromagnet Fe${}_{2.72}$GeTe${}_2$

Song Bao, Wei Wang, Yanyan Shangguan +12

In the local or itinerant extreme, magnetic excitations can be described by the Heisenberg model which treats electron spins as localized moments, or by the itinerant-electron mode…