LD热弛豫时间与泵浦光谱效率的改进

Improvement of thermal relaxation time and wavelength pumping efficiency of laser diode

采用测试半导体激光器热弛豫时间的新方法,测量光信号脉冲内不同时刻的时间分辨光谱,测试了 TO 封装和 cm-Bar 列阵的 AIGaAs/GaAs 半导体激光器泵浦光源,得到其热弛豫时间分别为为66μs和96μs。在目前常用的方波驱动电流脉冲工作条件下,半导体激光器作为固体激光器泵浦源,如果热弛豫时间过长,单个脉冲内激射波长会偏离固体激光介质的吸收带,导致泵浦光波长利用率和有效泵浦能量降低。为克服现有技术的不足,文中提出了两种新型的驱动电流脉冲波形,通过优化电流波形参数可以将泵浦波长利用率提高30%左右,得到更大的有效泵浦能量。

Using a new method,namely measuring time-resolved spectra during a current pulse,the thermal relaxation time parameters of a TO-can and a cm-Bar array AlGaAs laser diode(LD)used for pumping solid state lasers are measured to be 66 μs and 96 μs,respectively.With the regular rectangular injected current pulse,if the thermal relaxation time of the LD is too long,the lasing wavelength will deviate the absorbent spectrum of solid-state laser and the wavelength pumping efficiency and efficient pumping energy will be lower.In order to avoiding the shortcoming in foregoing technology,two new injected current pulse types are proposed.The wavelength pumping efficiency can be improved approximately 30% and the pumping energy will be much higher by optimizing several parameters of the new injected current pulses.