Fig. 4

Monolithic integration. a Robust laser operation at 80 °C with >1 M hour extrapolated lifetime. Adapted with permission from [84], copyright 2021, OPG. Individual QD lasers directly grown on silicon with b submilliamp threshold microring lasers, c mode-locked lasers, d coupled cavity tunable lasers and e DFB lasers. Adapted with permission from [85,86,87,88], copyright 2017 & 2019, OPG. f Schematic illustration of a selectively grown III–V cavity onto the handle wafer of an SOI substrate. Selective growth of box-shaped III-V materials on silicon for g a GaAs based nano-ridge laser array and h InP based DFB laser array. Adapted with permission from [89,90,91], copyright 2015 & 2017, OPG & NPG. i A monolithic offset QD integration platform where the light from QD active region is coupled to passive GaAs waveguides. Adapted with permission from [93], copyright 2020, OPG. j A regrown III-V QD-DFB laser that can combine different bandgaps into one optical chip. Adapted with permission from [94], copyright 2020, WILEY