大啁啾光纤布拉格光栅的脉冲响应特性研究

脉冲堆积技术是高功率激光系统中产生任意种子脉冲的方案之一.该方案利用大啁啾光纤布拉格光栅的宽带特性来展宽宽带短脉冲,以满足脉冲堆积组件的需求.利用传输矩阵法模拟了大啁啾宽带光纤布拉格光栅的反射谱、时延曲线等特性.研究发现,光纤光栅的啁啾因子决定了色散量以及带宽的大小,但增加色散量的代价是降低了光纤光栅的带宽;光栅长度越长,反射带宽明显增加,但色散量变化不大.研究结果对高功率前端系统的设计具有一定的指导意义.

Studies on the Pulse response Characters of Large Chirped Fiber Bragg Grating

The pulse-stacking technology is one of the schemes of generating arbitrary seed pulse in the high power laser system which is used to spread the broadband short pulse to satisfy the need of the pulse-stacking components due to the wideband character of the large chirped fiber Bragg grating (LCBG). The reflect spectrum and the time delay of LCBG were simulated through the transmission matrix method. As a result, the dispersion and bandwidth depend on the chirp factor of LCBG, but the cost to increase the dispersion is the reduced bandwidth. The results also show that the bandwidth would be increased remarkably with longer LCBG, but at the same time the dispersion was invariable. These results are significant for designing the front-end of the high power laser system.