Harnessing Optical Nonlinearities at milliWatt Power Levels for New Integrated Photonic Technologies

In the last 15 years there has been remarkable progress in boosting optical storage time in micro and millimeter-scale optical resonators. Chip-based devices attain Q factors of nearly 1 billion and micro-machined crystalline devices provide Qs exceeding 100 billion.  Extremely large resonant build-up effects are possible in these devices.  And these have created new perspectives for access to all nonlinear phenomena at milliWatt and even microWatt power levels.  Whole new classes of chip-integrated devices have resulted from this capability.  After reviewing the nonlinear physics of high-Q resonators, current work at Caltech on chip-based soliton microcombs and high-coherence Brillouin lasers will be discussed.  The application of these different phenomena to microcombs for optical frequency synthesis and miniature ring laser gyroscopes will be described.