• 文献标题:   Optical excitation of valley and spin currents of chiral edge states in graphene with Rashba spin-orbital coupling
  • 文献类型:   Article
  • 作  者:   LUO M, LI ZB
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   2469-9950 EI 2469-9969
  • 通讯作者地址:   Sun Yat Sen Univ
  • 被引频次:   4
  • DOI:   10.1103/PhysRevB.96.165424
  • 出版年:   2017

▎ 摘  要

Graphene on a substrate with a topological line defect possesses chiral edge states that exhibit linear dispersion and have opposite Fermi velocities for two valleys. The chiral edge states are localized at the line defect. With the presence of Rashba spin-orbital coupling, the dispersion of the chiral edge states splits into two. The optical excitation is modeled by the generalized semiconductor Bloch equation based on tight-binding theory. Charge, valley, and spin currents generated by normally incident plane waves through the photogalvanic effect as well as those generated by oblique light through the surface-plasmon drag effect are studied. Conditions for optical generation of purely localized valley or spin currents, which are solely originated from the chiral edge states, are discussed.