Static and Dynamic Response Analysis of Raman Injection Quantum Cascade Laser Using Circuit Level Modeling

In this paper a new approach for modeling of Raman quantum cascade lasers (QCLs) is presented which integrates electrical, optical and Raman effects. The equivalent circuit model of laser by employing simplified two-level rate equations of pump and Raman regions is developed. The total equivalent circuit is composed of pump laser circuit coupled to Raman laser circuit which models the behaviors of each component and whole device. By using the presented model the static and dynamic performances of laser for different parameters are investigated. The results of simulation show that the main characteristics of laser such as threshold current, quantum efficiency, output power and modulation response are affected by photon lifetime and variation of population inversion conditions. Static results of model agree favorably with experimental data from devices reported in the literatures.