Simulation of Carrier Dynamics in Multi-Quantum Well Lasers

We study the impact of carrier dynamics on the characteristics of InGaAsP/InP multi-quantum well lasers through detailed simulation and experiments. The device characteristics were simulated including carrier transport, capture of carriers into the quantum wells, quantum mechanical calculation of the levels and optical gain in the wells and solution for the optical mode. The simulations were self-consistent for each value of device bias. The device characteristics studied include static light-current-voltage curves, dynamic small signal impedance and the small signal modulation of the light output. The comparison between simulation and experiment constrains the capture rate for these devices. The simulations suggest that the modulation response of these devices is not fundamentally limited by the carrier transport for the frequency range studied. The trends are understood in terms of sequential transport through the multi-quantum well active region.