Hybrid integration of active semiconductor devices with passive micro/nano optical structures for emerging applications

We show a fully integrated, coherently combined laser system in the InP-Si3N4 hybrid platform. Coherent combining of two InP-based gain chips is obtained with a combining efficiency of ~92%. Besides, we demonstrate narrow-linewidth, tunable diode lasers in InP/GaAs-Si3N4 platform. The Si3N4 photonic integrated circuit performs as a tunable external cavity for both InP and GaAs gain chips simultaneously. Single frequency lasing at 1.55 and 1 um is simultaneously obtained on a single chip with the spectral linewidths of 18-kHz and 70-kHz respectively. We also obtain wide-angle beam steering by using the wide wavelength tuning range provided by dual-band diode lasers.