Hybrid laser with CMOS photonics

Abstract

In this thesis, an interesting approach for a photonic laser source is presented. By using integrated photonic resonators with an external gain medium, we are able to build a laser that offers a number of advantages including reducing the electrical and thermal load on the integrated chip socket, eliminating the challenges of integrating gain mediums into CMOS processes, allowing for lasing at virtually arbitrary wavelengths, the possibility of multiwavelength operation with a shared gain medium, elimination of closed-loop control of wavelength tuning, ability to control laser output and wavelength on-chip, and the potential for wavelength modulation using novel resonator tuning designs. Several iterations of the laser were built and characterized culminating in a final integrated laser that showed a wall-plug efficiency of 1.10% at a maximum output power of 6 mW. We demonstrate even higher wall-plug efficiencies using commercial filters. We also demonstrate wavelength modulation and open eye diagrams for data rates up to 5 Gb/s using the laser in a communications link. Simulations of birefringent filters are performed to model wavelength dependence on polarization which when manipulated can give rise to single or multiwavelength lasing. Finally, the power spectral density is simulated by assuming uncorrelated phase between lasing modes.