直接相位调制产生周期性线性啁啾脉冲特性研究

Periodic linear chirped pulse generation based on direct phase modulation

提出一种利用周期性抛物线调制信号对光脉冲进行相位调制以获得周期性线性啁啾脉冲的方法,并对其进行了数值模拟与实验研究.数值模拟结果表明:增益饱和效应、群速度色散以及同步误差对啁啾脉冲的时间-光谱特性影响较大;自相位调制对啁啾脉冲的影响较小.实验获得了0.52nm带宽的周期性线性啁啾脉冲,与模拟结果符合较好.实验结果同时表明装置中存在较大的偏振模色散,导致幅频效应较大,后续的研究中需加入对此的考虑.模拟及实验研究表明:直接相位调制是一种新型的可方便地获得周期性线性啁啾脉冲的方法,其在光谱色散平滑中具有潜在应用.

A new method of generating periodic linear chirped pulse is proposed,and a 0.52 nm bandwidth periodic chirped pulse is generated.Numerical simulation shows that the gain saturation,group velocity dispersion and synchronization jitter have great influences on chirped pulse;and self-phase modulation has little influence since the peak power stays at a low level.The experimental results indicate that the polarization mode dispersion will lead to a great intensity modulation,and the amplified spontaneous emission will break the light stability,which leads to the fewer round-trips of light.Research shows that the direct phase modulation is a novel method of generating periodic linear chirped pulse,which could be used for smoothing the spectral dispersion.