Skip to main content

Nonlinear optical conductivity of two-dimensional semiconductors with Rashba spin-orbit coupling in terahertz regime

Journal Article


Download full-text (Open Access)

Abstract


  • We reveal that two-dimensional semiconductors with Rashba spin-orbit interaction (R2DG) exhibit exceptionally strong nonlinear optical response (NOR) in the terahertz frequency regime. The spin-split of the parabolic energy band in R2DG allows strong multiple-photon process to occur via inter-subband mechanism. We show sharp multiple photon edges in the nonlinear conductivity. The edges correspond to the cut-off effect produced by the multiple-photon process. For Rashba coupling parameter of λ R ≈ 10−10 eV m, electric field strength in the order of only 102 V/cm is required for the NOR to dominate over the linear response. Furthermore, the roles of the parabolic ‘free electron’ term H 0 and the linear Rashba term H R on NOR of R2DG are also investigated. Although the NOR is made possible due to the presence of a finite H R , H 0 does play an important role on the NOR especially in high temperature regime. H 0 has rendered R2DG a strong optical nonlinearity at elevated temperature which is not found in a purely linear system such as graphene. The results suggest the possibilities of Rashba spintronic system in the application of nonlinear terahertz devices.

Authors


  •   Ang, Yee Sin S. (external author)
  •   Cao, Juncheng (external author)
  •   Chao Zhang

Publication Date


  • 2014

Citation


  • Ang, Y., Cao, J. C. & Zhang, C. (2014). Nonlinear optical conductivity of two-dimensional semiconductors with Rashba spin-orbit coupling in terahertz regime. European Physical Journal B: Condensed Matter and Complex Systems, 87 (28), 1-7.

Scopus Eid


  • 2-s2.0-84897731995

Ro Full-text Url


  • http://ro.uow.edu.au/cgi/viewcontent.cgi?article=1996&context=aiimpapers

Ro Metadata Url


  • http://ro.uow.edu.au/aiimpapers/995

Number Of Pages


  • 6

Start Page


  • 1

End Page


  • 7

Volume


  • 87

Issue


  • 28

Abstract


  • We reveal that two-dimensional semiconductors with Rashba spin-orbit interaction (R2DG) exhibit exceptionally strong nonlinear optical response (NOR) in the terahertz frequency regime. The spin-split of the parabolic energy band in R2DG allows strong multiple-photon process to occur via inter-subband mechanism. We show sharp multiple photon edges in the nonlinear conductivity. The edges correspond to the cut-off effect produced by the multiple-photon process. For Rashba coupling parameter of λ R ≈ 10−10 eV m, electric field strength in the order of only 102 V/cm is required for the NOR to dominate over the linear response. Furthermore, the roles of the parabolic ‘free electron’ term H 0 and the linear Rashba term H R on NOR of R2DG are also investigated. Although the NOR is made possible due to the presence of a finite H R , H 0 does play an important role on the NOR especially in high temperature regime. H 0 has rendered R2DG a strong optical nonlinearity at elevated temperature which is not found in a purely linear system such as graphene. The results suggest the possibilities of Rashba spintronic system in the application of nonlinear terahertz devices.

Authors


  •   Ang, Yee Sin S. (external author)
  •   Cao, Juncheng (external author)
  •   Chao Zhang

Publication Date


  • 2014

Citation


  • Ang, Y., Cao, J. C. & Zhang, C. (2014). Nonlinear optical conductivity of two-dimensional semiconductors with Rashba spin-orbit coupling in terahertz regime. European Physical Journal B: Condensed Matter and Complex Systems, 87 (28), 1-7.

Scopus Eid


  • 2-s2.0-84897731995

Ro Full-text Url


  • http://ro.uow.edu.au/cgi/viewcontent.cgi?article=1996&context=aiimpapers

Ro Metadata Url


  • http://ro.uow.edu.au/aiimpapers/995

Number Of Pages


  • 6

Start Page


  • 1

End Page


  • 7

Volume


  • 87

Issue


  • 28