I have been involved with the DARPA Direct On-Chip Digital Optical Synthesizer (DODOS) since it’s inception. My contribution is centered around supercontinuum generation and CEO detection, The slides for my latest talk at 2017 IEEE photonics conference can be downloaded here: IPC2017_malinowski.
From DARPA’s website:
“Since the first demonstration of optical frequency synthesis using self-referenced optical combs in 2000, demonstrations of novel civilian and defense applications for the technology have emerged worldwide. Due to the large size, relative fragility, and high cost of these components and systems, however, precise optical frequency synthesis so far has been limited to lab-scale experiments. DODOS aims to leverage recent breakthroughs in chip-scale mode-locked lasers and microresonators to enable self-referenced optical frequency combs in compact integrated packages. The program proposes to draw on recent progress in heterogeneous photonic integration to arrange all of the necessary components, including widely tunable laser sources, optical modulators, non-linear photonic elements, and CMOS radiofrequency (RF) and control circuitry onto a chip with a volume of less than 1 cm3 and power consumption of less than 1 Watt. The DODOS chip would act as a gearbox to directly translate the stability and accuracy of an RF signal to the optical domain, producing laser light at frequencies above 200 terahertz with relative accuracy of one part in 1015.”
This is a mode-locked laser that I have constructed to be used as a source for various nonlinear measurements such as supercontinuum and second harmonic generation. The mode-locked laser utilizes nonlinear-polarization rotation to achieve pulsed operation. After compression in an EDFA the pulse have a span of 120 fs at 90MHz repetition rate.