Over 1.65 GW cm^-2 sr^-1 brightness 590 nm yellow second-harmonic generation in MOCVD-grown high-strain InGaAs/GaAs...

High-brightness yellow lasers are in high demand for applications such as atomic cooling and trapping, optogenetics, and sodium laser guide stars. Herein, we demonstrate the potential of Metal-Organic Chemical Vapor Deposition (MOCVD) for the rapid mass production of high-strain 1.2 μm InGaAs quantum well vertical external cavity surface emitting lasers (VECSELs). Two distinct growth strategies were explored, with a primary focus on enhancing crystal thermal stability and mitigating indium segregation. The as-grown gain chips achieved over 45 W of output power and a slope efficiency exceeding 50%. Furthermore, we verified the feasibility of generating yellow second harmonic generation (SHG), attaining a 590 nm CW power of ~6.2 W with a slope efficiency of 17%. The beam quality factor (M²) was <1.1, approaching diffraction-limited performance, corresponding to a brightness of ~1.65 GW cm^-2 sr^-1. Overall, these investigations not only expand the performance envelope of MOCVD-grown semiconductor lasers but also deepen the understanding of indium segregation behaviors.