Fully-Stabilized Optical Frequency Comb System on a Chip

Over the past two decades, there has been rapid development of optical frequency comb technology with various applications including sensing, spectroscopy, data communications, positioning, and optical clocks. More recently, nanofabrication techniques adopted from the microelectronics industry have led to the realization of chip-scale frequency-comb sources. Our proposed efforts will focus on the development of hybrid integration of an integrated semiconductor amplifier and a silicon-nitride chip to create highly compact, robust modelocked lasers capable of producing pulses shorter than 100 femtoseconds. To date the shortest pulses that have been demonstrated from a chip-scale mode locked laser are 500 fs. We will overcome previous limitations by investigating and developing new types of chip-based artificial saturable absorbers that offer large differential loss and allow for generation of pulses as short as 100 femtoseconds. We will then demonstrate full self-referencing of this laser by determining the conditions for octave-spanning supercontinuum generation via integratinon with a dispersion-engineered waveguides. Ultimately, such a system would pave the way for highly compact, robust, and portable instruments based on optical frequency-comb technology.