Carrier tunneling and transport in coupled quantum wells: Modeling and experimental verification

We propose an approach to elucidate carrier dynamics by developing a robust rate equation model capable of explaining carrier dynamics in a dual-well system. To experimentally validate the accuracy and reliability of our model, we utilized a combination of time-resolved photoluminescence and spatially resolved cathodoluminescence measurements. The integration of these complementary techniques allowed us to thoroughly investigate the spectral characteristics in both wells, revealing distinct features attributed to carrier tunneling and transport effects and verifying the predictive ability of the model. This validation process not only confirms the model's accuracy under both coupled and uncoupled conditions but also highlights its potential applicability to quantum-well-based semiconductor lasers. Overall, our study not only advances our understanding of carrier dynamics in quantum wells but also introduces a versatile and reliable tool for designing and simulating ultrafast semiconductor lasers.