This paper studies the zero-electron-mass limit, the quasi-neutral limit and the zero-relaxation-time limit in one-dimensional hydrodynamic models of Euler-Poisson system for plasmas and semiconductors. For each limit...This paper studies the zero-electron-mass limit, the quasi-neutral limit and the zero-relaxation-time limit in one-dimensional hydrodynamic models of Euler-Poisson system for plasmas and semiconductors. For each limit in the steady-state models, the author proves the strong convergence of the sequence of solutions and gives the corresponding convergence rate. In the time-dependent models, the author shows some useful estimates for the quasi-neutral limit and the zero-electron-mass limit. This study completes the analysis made in [11,12,13,14,19].展开更多
文摘太赫兹倍频器是实现太赫兹源的重要途径之一。基于线性叠加技术,研制了0.38 THz单级无源四倍频单片。采用平面环形巴伦与正交混合网络级联的方式,设计了四路移相功分结构,通过零电长度合成,实现了单级四倍频,同时基波和其他无用谐波得到了很好的抑制。设计中先对无源结构进行三维电磁场仿真,然后与有源部分联合仿真优化,在370~410 GHz频率范围内,变频损耗小于25 d B。
文摘This paper studies the zero-electron-mass limit, the quasi-neutral limit and the zero-relaxation-time limit in one-dimensional hydrodynamic models of Euler-Poisson system for plasmas and semiconductors. For each limit in the steady-state models, the author proves the strong convergence of the sequence of solutions and gives the corresponding convergence rate. In the time-dependent models, the author shows some useful estimates for the quasi-neutral limit and the zero-electron-mass limit. This study completes the analysis made in [11,12,13,14,19].
