A CIRCUIT MODEL OF QUANTUM CASCADE LASERS APPLICABLE TO BOTH SMALL AND LARGE CURRENT DRIVES.

In this paper, a circuit model is devised to analyze nonlinear behaviour of quantum cascade lasers. Such nonlinear behavior influences the light output when the laser is driven by currents comparable to the average (DC) current. The simplified 2-level rate equations are first improved. Next, the circuit model is obtained following the approach for interband lasers. The difference between the circuit models of quantum cascade lasers and interband lasers is pointed out. The circuit model is simpler compared to that obtained from a 3-level model. Unlike a circuit model derived earlier from the 2-level model, the present model can handle both small and large current drives. [ABSTRACT FROM AUTHOR]