Signatures of interfacial topological chiral modes via RKKY exchange interaction in Dirac and Weyl systems

Abstract

We theoretically investigate the features of Ruderman-Kittel-Kasuya-Yosida (RKKY) exchange interaction between two magnetic impurities, mediated by the interfacial bound states inside a domain wall (DW). The latter separates the two regions with oppositely signed inversion symmetry broken terms in graphene and Weyl semimetal. The DW is modeled by a smooth quantum well which hosts a number of discrete bound states including a pair of gapless, metallic modes with opposite chiralities. We find clear signatures of these interfacial chiral bound states in spin response (RKKY exchange interaction) which is robust to the deformation of the quantum well.

Impurity-Induced Magnetization of Graphene

“…Magnetic interactions between these moments are depending on their specific location in the graphene sublattices and the density of free electrons (holes). Besides, the particularity of graphene electron structure makes it possible to appear an indirect RKKY interaction in the absence of free carriers through the polarization mechanism of electron-hole system [10]. As a result, magnetic interactions can be responsible for ferromagnetic or antiferromagnetic ordering of the moments [11].…”