Year: 2009
Type: article
Abstract: We investigate the effects of Rashba spin-orbit (RSO) 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 RSO interactions lift the quasidegeneracy 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 interaction proposed to exist in graphene are also presented.
Source: Physical Review B
Authors: Mahdi Zarea, Nancy Sandler
Institution: Ohio University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2012048872