This study demonstrates the growth of InAs quantum dots (QDs) on InP substrates using an all group III-arsenide approach in molecular beam epitaxy (MBE) with a low-indium-composition InAlGaAs partial capping layer. Real-time curvature measurements confirm effective strain compensation during multilayer QD growth, enabling precise control of emission wavelength and structural stability. The fabricated lasers exhibited successful operation at a telecommunication C-band.

This study investigates the development of InAs quantum dot (QD) lasers on a InP(001) substrate, utilizing only III-arsenide layers. This approach avoids the issues associated with the use of phosphorus compounds, which are evident in the crystal growth of conventional C/L-band QD lasers, making the manufacturing process safer, simpler, and more cost-effective. The threshold current density of the fabricated QD laser was 633 A/cm2, which is the lowest value for QD lasers in the 1.6 μm-wavelength region. This result suggests a high cost-effectiveness and paved the way toward a large-scale production technology for high-performing C/L/U-band QD lasers.