Comparison of Photocurrent Spectra of InGaAsN QD and InGaAs QW Laser Devices

An InGaAsN quantum dot (QD) laser structure and a reference InGaAs single quantum well (QW) laser structure were grown on GaAs substrates by metalorganic chemical vapor deposition. A comparison study of photocurrent spectra of these two structures was performed. It was found that InGaAsN QD devices exhibit a lower-energy transition and shows a smaller quantum-confined Stark effect than InGaAs QW devices. Also the wetting layer of InGaAsN QD devices shows a broader absorption peak than the InGaAs QW layer