半导体激光器在阈值处电学性质突变对应的物理图像

Physicals picture for discontinuous electrical behaviors of LDs at lasing threshold

对激光二极管(LDs)在阈值处不连续的电学特性作了详细分析,结果发现,各电学参量的突变之间存在紧密的内在关联。由表观IdV/dI-I曲线在阈值处的跳跃能直接得出结电导、结电压、串联电阻和理想化因子在阈值处的突变,因而证实传统的电学测量方法只能描述平均效果,忽略了各电参量随正向电流变化的详细信息。进一步实验表明,LDs在阈值附近的电特性的突变与光激射密切相关,这将为改进现有的LDs理论提供帮助。

From analyzing the discontinuous electrical behaviors of laser diodes（LDs） at lasing threshold in detail, it can be confirmed that the discontinuous electrical behaviors are the necessary results of the lasing of LDs.The sudden changes of junction voltage, series resistance and ideal factor of LDs at threshold could be directly deduced from the experimental IdV/dI-I curve.Compared with the ac small-signal method, the conventional electrical methods are proved to be very rough,and could not accurately characterize the dependences of LD parameters on forward current or voltage.Optical experiments show that the sudden changes of electrical parameters are closely related with lasing, which will help to improve the current theory of LDs.