English

Rash spin-orbit interaction in graphene and graphene zigzag nano-ribbons

Mesoscale and Nanoscale Physics 2009-05-08 v3

Abstract

We investigate the effects of Rashba spin-orbit interactions on the electronic band-structure and corresponding wave-functions of graphene. By exactly solving a tight-binding model Hamiltonian we obtain the expected splitting of the bands -due to the SU(2) spin symmetry breaking- that is accompanied by the appearance of additional Dirac points. These points are originated by valence-conduction band crossings. By introducing a convenient gauge transformation we study a model for zigzag nanoribbons with RSO interactions. We show that the RSO interactions lifts the quasi-degeneracy of the edge band while introducing a state-dependent spin separation in real space. Calculation of the average magnetization perpendicular to the ribbon plane suggest that RSO could be used to produce spin-polarized currents. Comparisons with the intrinsic spin-orbit (I-SO) interaction proposed to exist in graphene are also presented.

Keywords

Cite

@article{arxiv.0901.0160,
  title  = {Rash spin-orbit interaction in graphene and graphene zigzag nano-ribbons},
  author = {Mahdi Zarea and Nancy Sandler},
  journal= {arXiv preprint arXiv:0901.0160},
  year   = {2009}
}

Comments

minor changes, 10 figures