利用射线追踪法研究超短外腔半导体激光器的输出特性

基于射线追踪法，推导了外腔半导体激光器的连续输出谱的隐函表达式.在此基础上，结合载流子速率方程，对超短外腔半导体激光器的输出谱及P-I特性进行了研究.结果表明：当外腔长度发生波长量级的变化时，超短外腔激光器的P-I特性将发生显著变化；随着外腔长度的变化，超短外腔激光器的激射波长在10nm范围内呈周期性跳变，当外腔长度介于40μm—70μm范围内，激射波长跳变范围最大.理论模拟结果与实验报道结果符合.

Investigation of the output characteristics of extremely short external cavity semiconductor laser using the ray tracing method

Based on the ray tracing method，the implicit expression of the output spectrum of the extremely short external cavity semiconductor laser (ESECSL) has been deduced for the first time. As a result，the output spectrum and P-I characteristic of ESECSL have been investigated. The results show that: when the length of external cavity changes by an amount of the order of wavelength，the P-I characteristic of ESECSL will change obviously. The lasing wavelength of ESECSL will hop periodically in the range of 10nm with the variation of the length of external cavity. Especially，the hopping range of the lasing wavelength will reach the maximum for the external cavity length varying within the range of 40—70μm. The simulations are well in accordance with the experimental reports.