Graphene as a zero-bandgap two-dimensional semiconductor with a linear electron band dispersion near the Dirac points has the potential to exhibit very interesting nonlinear optical properties. In particular, third harmonic generation of terahertz radiation should occur due to the nonlinear relationship between the crystal momentum and the current density. In this work, we investigate the terahertz nonlinear response of graphene inside a parallel-plate waveguide. We optimize the plate separation and Fermi energy of the graphene to maximize third harmonic generation, by maximizing the nonlinear interaction while minimizing the loss and phase mismatch. The results obtained show an increase by more than a factor of 100 in the power efficiency relative to a normal-incidence configuration for a 2 terahertz incident field.
Adiabatic following of terahertz surface plasmon-polaritons coupler via two waveguides structure
最近，两篇引人注目的论文[New J. Phys. 21，113004（2019）; IEEE J. Sel. Top. Quantum Electron 27，1（2020）]提出了通过应用相干量子控制的宽带完全转移太赫兹（THz）表面等离子体激元（SPP）波导耦合器-受激拉曼绝热通道（STIRAP）。然而，以前的研究需要三个SPP波导耦合器。本文提出了一种新的宽带全转移太赫兹表面等离子体耦合器的设计，它采用了一种新颖的双波导结构，采用了两态绝热跟随。为了实现这一设计，我们首次在表面等离子体光波导的耦合方程中引入了失谐量。我们相信，这一发现将改善太赫兹通信领域。
Near-Field Coupling of Polypropylene Dielectric Waveguide Routed Near PCB Board at Terahertz Frequencies
School of Integrated Circuits and Electronic, Beijing Institute of Technology（北京理工大学集成电路与电子学院）；State Key Laboratory of Environment Characteristics and Effects for Near-space（临近空间环境特性及效应国家重点实验室）；School of Electronic and Information Engineering, Hebei University of Technology（河北工业大学电子信息工程学院）；Advanced Laser Technology Research Center（先进激光技术研究中心）
Dispersion Engineering of Planar Sub-millimeter Wave Waveguides and Resonators with Low Radiation Loss
University of Illinois at Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校）；The Grainger College of Engineering, University of Illinois Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校格雷恩格工程学院）
