A multi-wavelength array of hybrid silicon lasers and a method of fabricating such a device. The method may include providing a silicon-on-insulator wafer; patterning waveguides in the silicon-on-insulator wafer; providing a III-V wafer comprising multiple layers; applying quantum well intermixing to obtain a plurality of regions of different bandgaps within the III-V wafer; and bonding the silicon on insulator wafer with the III-V wafer.