Fe3GeTe2

Fe3GeTe2 is a layered intermetallic compound that belongs to the family of van der Waals–bonded transition-metal tellurides. It forms two-dimensional sheets that can be exfoliated to few-layer or monolayer thicknesses, enabling studies of magnetism and electronic properties in reduced dimensions.

The crystal structure comprises Fe-Ge-Te layers stacked along the c axis with van der Waals gaps between layers. Within each layer, iron atoms occupy sites coordinated by germanium and tellurium, creating a two-dimensional network that contributes to metallic conductivity and itinerant magnetic behavior. The overall crystal and electronic structure support strong magnetic anisotropy and complex coupling between spin and lattice degrees of freedom.

Magnetic and electronic properties indicate itinerant ferromagnetism in bulk samples, with a Curie temperature typically in the range of about 210–270 K. The magnetization tends to align along the c axis, reflecting easy-axis anisotropy. Reducing the material to thin films can modify the magnetic ordering and anisotropy, and ultrathin samples may exhibit ferromagnetism at lower temperatures. Fe3GeTe2 is metallic and shows a notable anomalous Hall effect and magnetoresistance linked to its ferromagnetic order. The combination of metallic behavior and ferromagnetism in a layered, exfoliable material has made it a focal point for studies of two-dimensional magnetism and spintronic phenomena.

Synthesis methods include chemical vapor transport and flux growth to produce high-quality bulk crystals, from which mechanical exfoliation yields few-layer flakes. Fe3GeTe2 is investigated for potential applications in spintronic devices, heterostructures with superconductors or topological materials, and as a platform for tuning magnetic properties via strain, doping, or electrical gating.