Nonlinear integrated photonics

This thesis focuses on the development and improvement of nonlinear integrated photonics platforms for use in high-capacity telecommunications.

The first part is about gallium nitride-on-sapphire integrated devices. The development of the platform and fabrication of the devices is described in detail and the results of both linear and nonlinear characterization is shown. Record-high (platform-specific) quality factors are demonstrated for the microring resonators as well as record high effective nonlinearity (again platform-specific) for the waveguides. The intrinsic material nonlinearity at telecom wavelengths is also extracted.

The second part concerns the aluminum gallium arsenide-on-insulator platform. A couple of specific attempts of improving the platform are described including atomic force microscopy of the sidewalls and surface passivation and the results of these efforts are presented.
Record-high data rate wavelength conversion (40 Gbit/s) using an integrated aluminum gallium arsenide-on-insulator microring resonator is also shown. The low power limit for successful conversion of a 10 Gbit/s signal is also tested.
Finally, the result of broadening of an electro-optic modulated comb in an aluminum gallium arsenide-on-insulator waveguide is shown.