Local magnetic moment oscillation around an Anderson impurity on graphene

Abstract

We theoretically investigate the spin resolved Friedel oscillation (FO) and quasiparticle interference (QPI) in graphene induced by an Anderson impurity. Once the impurity becomes magnetic, the resulted FO becomes spin dependent, which gives rise to a local magnetic moment oscillation with an envelop decaying as r⁻² in real space in the doping cases. Meanwhile, at half filling, the electron density and local magnetic moment will not oscillate but decay as r⁻³. Such spin resolved FO has both sublattice and spin asymmetry. Interestingly, the local magnetic moment decay at half filling only occurs at one sublattice of graphene, which is quite like the phenomenon observed in the STM experiment (H. González-Herrero et al., Science 352, 437 (2016)). We further give an analytic formula about such spin dependent FO based on the stationary phase approximation. Finally, we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states (FT-LDOS). Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.