GaAs光电导开关非线性锁定效应的机理研究  

Lock-on Mechanism in Nonlinear Mode of Photoconductive Switches

作　　者：薛红[1,2] 施卫[1] 纪卫莉[1] 韩小卫[1,2] 

机构地区：[1]西安理工大学理学院,陕西西安710054 [2]渭南师范学院物理系,陕西渭南714000

出　　处：《西安理工大学学报》2011年第4期407-410,共4页Journal of Xi'an University of Technology

基　　金：国家重点基础研究发展计划(973计划)资助项目(2007CB310406);国家自然科学基金资助项目(50837005;10876026)

摘　　要：根据光激发电荷畴模型,研究强电场条件下,半绝缘GaAs光电导开关体内热电子的瞬态输运过程及载流子与晶格相互作用的性质,并对光激发单极电荷畴的形成、生长、输运及达到稳定平衡状态的全过程进行了分析。认为GaAs光电导开关的非线性锁定效应是光激发单电荷畴处于稳定平衡状态时的必然结果,同时,电荷畴内部及前端的强电场区域伴随有热电子强烈的局部碰撞电离和辐射复合作用,使载流子迅速"雪崩"倍增,形成输出电脉冲的超快上升沿,强电场区出现在GaAs光电导开关的阳极周围,在电荷畴到阳极之间将发生强烈的碰撞电离和辐射复合发光,形成丝状电流。According to photo-activated charge domain model,the transient transport processes of hot electrons and the nature of carriers-lattice interaction in the semi-insulating GaAs photoconductive switches with an ultrahigh electric fields is discussed;and the processes of producing and growth and achieved stable equilibrium state on photo-activated monopole domain is analyzed in details.The results indicate that the Lock-on effect in nonlinear mode of photoconductive switches is a stable equilibrium state of photo-activated charge domain（monopole domain）,and simultaneously there are the strong local impact ionization and radiative recombination effect of hot electrons in the ultrahigh electric field internal and front-end of the monopole domain,where by making carriers ＂avalanche＂ quickly in multiplication and output electric pulse rising rapidly,the ultrahigh electric field appears near the anode region of GaAs photoconductive switches and strong impact ionization and radiative recombination of the hot electrons will occur so as to form current filaments.

关 键 词：光电导开关 锁定效应 光激发单极电荷畴 非平衡载流子 

分 类 号：TN256[电子电信—物理电子学]