Rashba-like Spin Textures in Graphene Promoted by Ferromagnet-Mediated Electronic Hybridization with a Heavy Metal.

Epitaxial graphene/ferromagnetic metal (Gr/FM) heterostructures deposited onto heavy metals have been proposed for the realization of spintronic devices because of their perpendicular magnetic anisotropy and sizable Dzyaloshinskii-Moriya interaction (DMI), allowing for both enhanced thermal stability and stabilization of chiral spin textures. However, establishing routes toward this goal requires the fundamental understanding of the microscopic origin of their unusual properties. Here, we elucidate the nature of the induced spin-orbit coupling (SOC) at Gr/Co interfaces on Ir.

Temperature Dependence of Relativistic Valence Band Splitting Induced by an Altermagnetic Phase Transition.

Altermagnetic (AM) materials exhibit non-relativistic, momentum-dependent spin-split states, ushering in new opportunities for spin electronic devices. While the characteristics of spin-splitting are documented within the framework of the non-relativistic spin group symmetry, there is limited exploration of the inclusion of relativistic symmetry and its impact on the emergence of a novel spin-splitting in the band structure. This study delves into the intricate relativistic electronic structure of an AM material, α-MnTe.

Experimental Realization of a Three-Dimensional Dirac Semimetal Phase with a Tunable Lifshitz Transition in Au_{2}Pb.

Three-dimensional Dirac semimetals are an exotic state of matter that continue to attract increasing attention due to the unique properties of their low-energy excitations. Here, by performing angle-resolved photoemission spectroscopy, we investigate the electronic structure of Au_{2}Pb across a wide temperature range. Our experimental studies on the (111)-cleaved surface unambiguously demonstrate that Au_{2}Pb is a three-dimensional Dirac semimetal characterized by the presence of a bulk Dirac cone projected off-center of the bulk Brillouin zone (BZ), in agreement with our theoretical calculations.

Inducing Single Spin-Polarized Flat Bands in Monolayer Graphene.

Due to the fundamental and technological implications in driving the appearance of non-trivial, exotic topological spin textures and emerging symmetry-broken phases, flat electronic bands in 2D materials, including graphene, are nowadays a relevant topic in the field of spintronics. Here, via europium doping, single spin-polarized bands are generated in monolayer graphene supported by the Co(0001) surface. The doping is controlled by Eu positioning, allowing for the formation of a -valley localized single spin-polarized low-dispersive parabolic band close to the Fermi energy when Eu is on top, and of a π* flat band with single spin character when Eu is intercalated underneath graphene.

Visualizing Higher-Fold Topology in Chiral Crystals.

Novel topological phases of matter are fruitful platforms for the discovery of unconventional electromagnetic phenomena. Higher-fold topology is one example, where the low-energy description goes beyond standard model analogs. Despite intensive experimental studies, conclusive evidence remains elusive for the multigap topological nature of higher-fold chiral fermions.