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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 …
Chiral-Like Tunneling Of Electrons In Two-Dimensional Semiconductors With Rashba Spin-Orbit Coupling, Yee Sin Ang, Zhongshui Ma, C Zhang
Chiral-Like Tunneling Of Electrons In Two-Dimensional Semiconductors With Rashba Spin-Orbit Coupling, Yee Sin Ang, Zhongshui Ma, C Zhang
Yee Sin Ang
The unusual tunneling effects of massless chiral fermions (mCF) and massive chiral fermions (MCF) in a single layer graphene and bilayer graphene represent some of the most bizarre quantum transport phenomena in condensed matter system. Here we show that in a two-dimensional semiconductor with Rashba spin-orbit coupling (R2DEG), the real-spin chiral-like tunneling of electrons at normal incidence simultaneously exhibits features of mCF and MCF. The parabolic branch of opposite spin in R2DEG crosses at a Dirac-like point and has a band turning point. These features generate transport properties not found in usual two-dimensional electron gas. Albeit its p Berry phase, …
Nonlinear Optical Spectrum Of Two-Dimensional Electron Gas With Rashba Spin-Orbit Interaction In Thz Frequency Regime, Yee Sin Ang, C Zhang, Qinjun Chen
Nonlinear Optical Spectrum Of Two-Dimensional Electron Gas With Rashba Spin-Orbit Interaction In Thz Frequency Regime, Yee Sin Ang, C Zhang, Qinjun Chen
Yee Sin Ang
We theoretically calculate the nonlinear optical spectrum of two-dimensional electron gas in the presence of Rashba spin-orbit interaction in terahertz frequency regime. For Rashba coupling parameter in the order of 0.4 eVÅ, the nonlinear optical response exceeds the linear response with the application of an external electric field strength in the order of 103 V/cm.