3 research outputs found
Localized magnetic states in biased bilayer and trilayer graphene
We study the localized magnetic states of impurity in biased bilayer and
trilayer graphene. It is found that the magnetic boundary for bilayer and
trilayer graphene presents the mixing features of Dirac and conventional
fermion. For zero gate bias, as the impurity energy approaches the Dirac point,
the impurity magnetization region diminishes for bilayer and trilayer graphene.
When a gate bias is applied, the dependence of impurity magnetic states on the
impurity energy exhibits a different behavior for bilayer and trilayer graphene
due to the opening of a gap between the valence and the conduction band in the
bilayer graphene with the gate bias applied. The magnetic moment and the
corresponding magnetic transition of the impurity in bilayer graphene are also
investigated.Comment: 16 pages,6 figure
Charge and spin Hall effect in graphene with magnetic impurities
We point out the existence of finite charge and spin Hall conductivities of
graphene in the presence of a spin orbit interaction (SOI) and localized
magnetic impurities. The SOI in graphene results in different transverse forces
on the two spin channels yielding the spin Hall current. The magnetic
scatterers act as spin-dependent barriers, and in combination with the SOI
effect lead to a charge imbalance at the boundaries. As indicated here, the
charge and spin Hall effects should be observable in graphene by changing the
chemical potential close to the gap.Comment: 7 page