摘要
对 Ga As光导开关非线性工作时 ,负微分迁移率和碰撞电离的作用进行了数值分析 ,给出了考虑和未考虑碰撞电离作用时的外电路电流输出波形 ,以及载流子和电场的空间分布和随时间演变的情况。计算表明 Ga As材料的负微分迁移率引起的微分负阻 ,会导致阴极附近电场的动态增强 ,使得阴极附近的电场达到本征碰撞电离发生的阈值电场 ,从而引发本征碰撞电离的发生。分析结果表明 ,碰撞电离可以极大地延长电流输出的时间 ,但仅考虑负微分迁移率特性的本征碰撞电离过程不足以完全解释观察到的所有非线性现象 。
The role of negative differential mobility and impact ionization in nonlinear operation of PCSS is analyzed.The output current profiles with and without impact ionization are presented.The spatial distribution and temporal evolution of electric field and current density are also presented.The simulation results show that the negative differential resistance due to negative differential mobility of GaAs lead to electric field enhancing enough near cathode to give rise impact ionization.It shows that impact ionization prolong conduction time.However,it is not enough only negative differential mobility and impact ionization to be considered to explain all nonlinear phenomena observed experimentally.
出处
《光子学报》
EI
CAS
CSCD
北大核心
2002年第4期445-449,共5页
Acta Photonica Sinica
基金
国家自然科学基金资助项目 ( 6 9781 0 0 2 )
