宽可调谐双微环耦合半导体激光器的模拟研究

为了对宽可调谐微环耦合半导体激光器进行理论研究,提出了一种新型半导体激光器动态理论模型对其动态特性进行仿真分析。激光器的有源区采用传统的时域行波法进行模拟,由于调谐带宽大于40nm,需要考虑增益谱线型,而无源区则先利用频域模型计算其频谱特性,再利用有限冲击响应数字滤波器转化到时域与有源区进行连接。通过仿真分析得出,微环的耦合系数对激光器的大信号调制具有十分重要的影响。低耦合系数可以获得极窄的线宽但是激光器大信号直接调制能力也会随之急剧劣化。仿真结果还显示出该类型激光器可以进行高速大范围波长调谐。

Modeling of Widely Tunable Double-Ring-Resonator Coupled Semiconductor Laser

A relatively simple model is developed to simulate the widely tunable double-ring resonator lasers. In the simulation, the active region of the device is modeled using conventional time domain traveling method, because when the tuning range is large than 40 nm, the gain shape should be considered. The passive parts are first modeled by frequency domain method and then transformed into time domain via digital filter. The simulation result shows that the coupling coefficient has a significant effect on large signal modulation. With low coupling coefficient the laser can get narrow linewidth but poor modulation performance. Finally, the switching characteristics such as switching delay and multi-mode competition are also investigated. The result shows that the laser can switch the wavelength with high speed and large range.