Thermoelectric properties of magnetic configurations of graphene-like nanoribbons in the presence of Rashba and spin–orbit interactions

• Published in: Physica. E, Low-dimensional systems & nanostructures Low-dimensional systems & nanostructures, 2017-03, Vol.87, p.220-227
• Main Author: Wierzbicki, Michal
• Format: Article
• Language: English
• ISSN: 1386-9477; 1873-1759
• DOI: 10.1016/j.physe.2016.10.033

In this paper we investigate the influence of spin–orbit interaction and two types of Rashba interaction (intrinsic and extrinsic) on magnetic and thermoelectric properties of graphene-like zigzag nanoribbons based on the honeycomb lattice. We utilize the Kane-Mele model with additional Rashba interaction terms. Magnetic structure is described by the electron-electron Coulomb repulsion reduced to the on-site interaction (Hubbard term) in the mean field approximation. We consider four types of magnetic configurations: ferromagnetic and antiferromagnetic with in-plane and out-of plane direction of magnetization. Firstly, we analyze the influence of extrinsic Rashba coupling on systems with negligible spin–orbit interaction, e.g. graphene of an appropriate substrate. Secondly, we discuss the interplay between spin–orbit and intrinsic Rashba interactions. This part is relevant to materials with significant spin–orbit coupling such as silicene and stanene. •Large Rashba coupling favors ferromagnetic configuration of graphene-like nanoribbons.•In the presence of external Rashba coupling there appear both in-plane and out-of-plane spin currents.•Internal Rashba coupling in the presence of large spin-orbit interaction affects spin-current, however does not influence spin thermoelectric effects.