Weyl Semimetallic State in the Rashba–Hubbard Model

The impact of Rashba spin-orbit coupling in charge-ordered systems

“…On the other hand, in the absence of EPC (g = 0), the RSOC splits the spin textures-see, e.g. figures 1(a) and (c), shifting the vHs away from the half-filling, while preserving the FSN [47,48]. This gives rise to instabilities in the particlehole channel, except when t/t R = 0, where a WSM emerges.…”

“…Then, it is imperative to compare these cases with ours, highlighting both their similarities and differences. For instance, for the repulsive Hubbard model in the half-filled square lattice, the inclusion of the RSOC leads to the emergence of novel magnetic phases, which may include spiral and striped ones; away from the half-filling, ferromagnetism may appear [47,48,58,59,[61][62][63]. This occurs due to the spin-flip term in the RSOC, which disfavors the staggered antiferromagnetic ground state of the half-filling, suppressing the charge gap, while keeping gapless spin excitations.…”

“…At this point, we have to recall that, for θ = π/2, the Dirac cones are nested for both Q = (π, π) and Q = (0, π) wavevectors, which could lead to striped phases. Indeed, in the Rashba-Hubbard model, a (0, π)-striped antiferromagnetic phase emerges around θ = π/2 [48]. Therefore, it is worth investigating the stabilization of the CDW order for different wavevectors Q = (q x , q y ).…”

“…In contrast with the MFT solution, the emergence of a Rashba metal within the CPT approach is an intriguing issue, particularly because of the occurrence of FSN instabilities [48,57]. For the Rashba-Hubbard model, clusters methodologies also exhibit such a correlated Rashba metal phase, which is justified by nontrivial renormalizations of the kinetic terms, induced by changes in the spectral weights when strong electronic interactions are present [58,59].…”