Carrier dynamics and microwave characteristics of GaAs-based quantum-well lasers

We investigate the effects of carrier capture and re-emission on the electr ical impedance, equivalent circuit, and modulation response of quantum-well (QW) laser diodes. The electrical impedance is shown to be a sensitive fun ction of the time constants associated with carrier capture/transport and c arrier re-emission. We compare the theoretical results with measured values of the electrical impedance of high-speed InGaAs-GaAs multiple-quantum-wel l lasers fabricated using different epilayer structures with a common later al structure. The experimental results agree well with the theoretical mode l, allowing us to extract the effective carrier escape time and the effecti ve carrier lifetime in the QW's, and to estimate the effective carrier capt ure/transport time.