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Full-Text Articles in Engineering
Nonlinear Optical Conductivity Of Two-Dimensional Semiconductors With Rashba Spin-Orbit Coupling In Terahertz Regime, Yee Sin Ang, J C. Cao, Chao Zhang
Nonlinear Optical Conductivity Of Two-Dimensional Semiconductors With Rashba Spin-Orbit Coupling In Terahertz Regime, Yee Sin Ang, J C. Cao, Chao Zhang
Yee Sin Ang
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 …
Nonlinear Optical Properties Of Bilayer Graphene In Terahertz Regime, Yee Sin Ang, S Sultan, Rodney Vickers, Chao Zhang
Nonlinear Optical Properties Of Bilayer Graphene In Terahertz Regime, Yee Sin Ang, S Sultan, Rodney Vickers, Chao Zhang
Yee Sin Ang
We have carried out a theoretical and computation study of optical response of bilayer graphene in the terahertz regime. It is found that the optical response of bilayer graphene can be significantly enhanced by nonlinear process for fields greater than 1000v/cm. The optical nonlinearity of bilayer graphene persists even in room temperature. This suggests that bilayer graphene can potentially be utilized as a temperature-robust nonlinear material in the terahertz regime.
Intraband Nonlinear Terahertz Waves Absorption Of Gapped Graphene, Asya Tawfiq, Yee Sin Ang, Chao Zhang
Intraband Nonlinear Terahertz Waves Absorption Of Gapped Graphene, Asya Tawfiq, Yee Sin Ang, Chao Zhang
Yee Sin Ang
The effect of bandgap opening on the intraband nonlinear optical response of graphene in terahertz frequency regime is theoretically investigated. The nonlinear optical response of gapped graphene is found to be sensitively influenced by the bandgap level and temperature. © 2012 IEEE.
Strong Nonlinear Optical Response Of Bilayer Graphene In The Terahertz Regime, Yee Sin Ang, Chao Zhang
Strong Nonlinear Optical Response Of Bilayer Graphene In The Terahertz Regime, Yee Sin Ang, Chao Zhang
Yee Sin Ang
We demonstrate that bilayer graphene exhibits strong nonlinear optical response in the terahertz frequency regime.The electric field strength required to generate single-frequency and triple-frequency nonlinear optical responses comparable to the linear optical response is only moderate and can be easily achieved in laboratory.This strong nonlinear optical response persists even in room temperature.This suggests that bilayer graphene can potentially be utilized in nonlinear terahertz photonics
Nonlinear Optical Response Of Graphene Superlattice In Terahertz Frequency Regime, Yee Sin Ang, Chao Zhang
Nonlinear Optical Response Of Graphene Superlattice In Terahertz Frequency Regime, Yee Sin Ang, Chao Zhang
Yee Sin Ang
We investigate the nonlinear optical response of a Kronig-Penney type graphene superlattice in which the Fermi velocity of the massless Dirac quasiparticle anisotropically depends on the direction of propagation. Such velocity anisotropy results in enhanced nonlinear optical response in terahertz frequency regime.