隔离电阻对集成光源特性的影响分析

Dependence of the Characteristics of the Integrated Laser-modulator on the Isolation Resistance

提出了一种分布反馈(DFB)激光器与电吸收(EA)调制器集成光源(EML)的等效电路模型。该模型考虑了由于隔离电阻不够大而导致的激光器与调制器之间的电耦合,通过对电路模型进行仿真可以看出,对于不同隔离电阻的EML,激光器的阈值电流、调制器的频率响应带宽、集成器件的小信号调制和脉冲调制等多方面特性均有明显不同。分析得到,EML的隔离电阻阻值只有达到10 kΩ量级,才能够忽略电泄漏对器件特性的影响。并指出EML在更高的偏置下,将对隔离电阻提出更高的要求。

A circuit model of an integrated laser-modulator (EML) was presented. Electrical interactions between the distributed feedback (DFB) laser and the electroabsorption (EA) modulator are taken into account in this model. The simulation is focused on the dependence of the characteristics of the integrated laser-modulator on the isolation resistance between the DFB laser and EA modulator. Great differences for the characteristics of the integrated light sources with different isolation resistances were shown in the simulations. An isolation resistance of 10 kΩ is required by the integrated device researched. The optimal design for the isolation resistance at different bias had been discussed.