Local moment formation in bilayer graphene

TL;DR

This paper investigates how the local magnetic properties of impurities in bilayer graphene vary depending on the sublattice they are adsorbed on, revealing potential for spintronic applications.

Contribution

It applies the Anderson impurity model to analyze sublattice-dependent local moment formation in bilayer graphene, highlighting the influence of spatial inhomogeneity.

Findings

Impurities on A sublattice can magnetize even with high impurity levels and low Coulomb energy.

Impurities on B sublattice magnetize only within limited parameter ranges.

Electrical control of impurity magnetization suggests potential for spintronic devices.

Abstract

The local properties of bilayer graphene (BLG) due to the spatial inhomogeneity of its sublattices are of interest. We apply Anderson impurity model to consider the local moment formation on a magnetic impurity which could be adsorbed on different sublattices of BLG. We find different features for the impurity magnetization when it is adsorbed A and B sublattices. The impurity adsorbed on A sublattice can magnetize even when the impurity level is above the Fermi level and the on-site coulomb energy is very small. But when the impurity is adsorbed on B sublattice the magnetization is possible for limited values of the impurity level and the on-site coulomb energy. This is due to different local density of the low energy states at A and B sublattices which originates from their spatial inhomogeneity. Also we show that electrical controlling the magnetization of adatoms besides it's inhomogeneity in BLG allow for possibility of using BLG in spintronic devices with higher potential than graphene.