RKKY coupling in graphene

Details RKKY coupling in graphene RKKY coupling in graphene

2010-01-22

arxiv.org/abs/1001.4024v2

Phys. Rev. B 80, 205416 (2010)

Physics

Condensed Matter

Mesoscale and Nanoscale Physics

8 pages, 6 figures

Scientific paper

We study the carrier-mediated exchange interaction, the so-called RKKY coupling, between two magnetic moments in graphene using exact diagonalization on the honeycomb lattice. By using the tight-binding nearest neighbor band structure of graphene we avoid the use of a momentum cut-off which plagues results in the Dirac continuum model formulation. We extract both the short and long impurity-impurity distance behavior and show several corrections to earlier long distance results. In the bulk the RKKY coupling is proportional to $1/|{\bf R}|^3$ and displays $(1+\cos(2{\bf k}_D\cdot {\bf R})$-type oscillations. A-A sublattice coupling is always ferromagnetic whereas A-B subattice coupling is always antiferromagnetic and three times as large. We also study the effect of edges in zigzag graphene nanoribbons (ZGNRs) and find that for impurities on the edge, the RKKY coupling decays exponentially because of the localized zero energy edge states. For impurities inside a ZGNR the bulk characteristics are quickly regained.

Affiliated with

Also associated with

No associations

Rating

RKKY coupling in graphene does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with RKKY coupling in graphene, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and RKKY coupling in graphene will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-656141