CARRIER DYNAMICS IN InGaN MQW STRUCTURE WITH VARYING EMISSION WAVELENGTHS

InGaN is a semiconductor extensively used in optoelectronic applications, including LEDs and laser diodes due to its high mobility, good internal quantum efficiencies and tunable bandgap. To this day, nitride-based light emitting devices face challenges such as efficiency drop at high carrier densities and reduction in internal quantum efficiency in the green wavelength region, known as the "green gap”, which hinders the production of high-efficiency green light devices. Despite these challenges, InGaN remains as a leading candidate for covering the entire visible spectrum, making it critical to study the effects of variations in indium content and QW width on these structures. In this study, we investigate the non-equilibrium carrier dynamics of an InGaN MQW sample with spatial variations in indium content, using light-induced transient grating and time-integrated photoluminescence techniques. By analyzing lifetime, diffusivity, and diffusion length properties, we establish their relationship with internal quantum efficiency and model the carrier dynamics with a modified ABC model. This study reveals how carrier dynamics in InGaN QWs change with varying emission wavelengths with variations in indium content and QW width, while keeping other factors constant. Our findings show a decreasing trend in the recombination rates of different channels at longer wavelengths.