Relating spin-polarized STM imaging and inelastic neutron scattering in the van-der-Waals ferromagnet Fe3GeTe2

Abstract

Van-der-Waals (vdW) ferromagnets have enabled the development of heterostructures assembled from exfoliated monolayers with spintronics functionalities, making it important to understand and ultimately tune their magnetic properties at the microscopic level. Information about the magnetic properties of these systems comes so far largely from macroscopic techniques, with little being known about the microscopic magnetic properties. Here, we combine spin-polarized scanning tunneling microscopy and quasi-particle interference imaging with neutron scattering to establish the magnetic and electronic properties of the metallic vdW ferromagnet Fe3GeTe2. By imaging domain walls at the atomic scale, we can relate the domain wall width to the exchange interaction and magnetic anisotropy extracted from the magnon dispersion as measured in inelastic neutron scattering, with excellent agreement between the two techniques. From comparison with Density Functional Theory calculations we can assign the quasi-particle interference to be dominated by spin-majority bands. We find a dimensional dichotomy of the bands at the Fermi energy: bands of minority character are predominantly two-dimensional in character, whereas the bands of majority character are three-dimensional. We expect that this will enable new design principles for spintronics devices.

18 pages main manuscript with 5 figures plus 12 pages supplementary

References in corpus (6)

• Dirac magnons in honeycomb ferromagnets
• Quasiparticle Interference of the van-Hove singularity in Sr${}_2$RuO${}_4$
• Interlayer magnetism in Fe3-xGeTe2
• Non-reciprocal magnons in a two dimensional crystal with off-plane magnetization
• Preparation of magnetic tips for spin-polarized STM on Fe_{1+y}Te
• Magnetic surface reconstruction in the van-der-Waals antiferromagnet Fe${}_{1+x}$Te

Cited by in corpus (6)

• Antiferromagnetic fluctuations and orbital-selective Mott transition in the van der Waals ferromagnet Fe3-xGeTe2
• Proposal for all-electrical skyrmion detection in van der Waals tunnel junctions
• A new inelastic neutron spectrometer HODACA
• Direct evidence from high-field magnetotransport for a dramatic change of quasiparticle character in van der Waals ferromagnet Fe${}_{3-x}$GeTe${}_2$
• Direct observation of interfacial exchange coupling in a magnetic tunnel junction through spin-polarized quasiparticle interference
• Signatures of Kondo-lattice behavior in the two-dimensional ferromagnet Fe${}_3$GeTe${}_2$