Magnetic correlations in the quasi-2D itinerant ferromagnet Fe3-xGeTe2

Compounds with two-dimensional (2D) layers weakly connected by van der Waals bonds offer access to novel physics via quantum confinement and are potential routes to new device applications. Neutron scattering can provide a powerful probe of these bulk quasi-2D materials, giving quantitiative insights into magnetic exchange interactions, low dimensionality and magnetostructural coupling. This understanding of the bulk material behavior affords insight into the important underlying interactions in these compounds and provides routes to understanding the materials down to a single 2D-monolayer. Here we present neutron scattering results on the quasi-2D itinerant ferromagnetic Fe3-xGeTe2. The neutron scattering results reveal insights into the magnetic correlations, 2D phenomena, magnetic anisotropy and short range ordering.