970 nm高功率光栅外腔可调谐半导体激光器

High Power 970 nm Semiconductor Laser With A Tunable Grating External Cavity

宽条形半导体激光器广泛应用于激光泵浦、激光加工等领域。针对宽条型半导体激光器输出光谱宽、调谐范围小的问题,采用衍射效率分别为28%和55%的反射式衍射光栅作为反馈元件构建了宽条形970 nm波长光栅外腔半导体激光器。研究了Littrow结构激光器参数对其性能(调谐范围、功率、阈值电流、线宽)的影响。实验结果表明,通过结构优化可得到窄线宽可调谐激光输出,适当地提高温度和使用较高衍射效率的光栅可增加激光器调谐范围,并且较高衍射效率的光栅可降低激光器的阈值电流。基于S偏振入射方式的光栅外腔激光器最大可实现27.87 nm的波长调谐范围,光谱线宽压窄至0.2 nm,输出功率可达1.11 W。

Broad-area stripe semiconductor lasers are widely used in laser pumping,laser processing and other fields.In order to solve the problems of wide output spectrum and small tuning range of broad-area stripe semiconductor lasers,reflective diffraction grating with diffraction efficiency of 28%and 55%was used as a feedback element to construct a broad-area 970 nm semiconductor laser with a grating external cavity.The effect of the parameters of semiconductor laser with a grating external cavity in Littrow configuration on its performance(tuning range,power,threshold current,linewidth)was investigated.The experimental results show that the tunable laser output with narrow linewidth can be obtained by optimizing the structure,the tuning range of the outer cavity laser can be increased by increasing the temperature appropriately,the tuning range of the outer cavity laser can be improved and the threshold current can be reduced by using a grating with higher diffraction efficiency.The maximum wavelength tuning range of semiconductor laser with a grating external cavity based on S-polarization is 27.87 nm,the spectral linewidth pressure is narrowed to 0.2 nm,and the output power can reach 1.11 W.