光纤Bragg光栅的慢光特性

运用数值计算的方法研究了光栅长度和调制深度对光纤Bragg光栅慢光的影响,并重点分析了优化后的慢光特性。结果表明：随着光栅长度和调制深度的增大,光纤Bragg光栅的慢光群时延量不断增大,增长的幅度也在逐渐增大;且一定带宽的谐振峰两边的旁瓣加强;同时谱底趋向平坦。调制深度的增大使其慢光峰值波长产生红移,短波长处的慢光群时延量往相反方向增大,且慢光谱的谱宽也增大。优化参数后得到了群速度为c/98的慢光,且慢光谱中心频率的右侧边带产生了很大的振动。这些规律可为设计新型的慢光延迟器件提供理论参考。

Slow Light Characteristics of Fiber Bragg Gratings

The influence of grating length and fringe visibility for slow light of fiber Bragg gratings were investigated by numerical simulation method,and slow light after optimizing the parameters was proposed emphatically.The results showed that the slow light delay increases with grating length and modulation depth,and change rates increases gradually.A certain bandwidth of resonance peaks on both sides of the side lobe and the peak top become extremely flattened.The slow light delay curves are red-shifted and short wave strengths increase to the opposite direction.The right side of the center frequency spectrum side band has a great vibration.By optimizing the structure parameters,the maximum group velocity can be lowed to c/98.This provides theoretical basis for designing the slow light devices based on fiber Bragg gratings.