High-performance photonics for defense takes a giant step forward, study saysNews
June 26, 2020
SANTA BARBARA, Calif. A new result published in the journal Nature by a team of academic researchers led by University of California at Santa Barbara (UCSB) demonstrates stable, turnkey operation of chipscale optical frequency combs, which means that component makers are a giant step closer toward enabling broader manufacture and use of high-performance photonics for defense and other use.
DARPA [Defense Advanced Research Projects Agency] launched the Direct On-Chip Digital Optical Synthesizer (DODOS) program in 2014 to address the dilemma of optical frequency synthesizers, which have largely been limited to laboratory settings due to the cost, size, and power requirements of their components. To reduce these obstacles to widespread use, the DODOS program aims to miniaturize the necessary components and their integration into a compact module, thereby enabling broader deployment of the technology while unlocking new applications.
DARPA and DODOS are attempting to leverage advances in microresonators – the tiny structures that store light in microchips – to produce optical frequency combs in compact integrated packages; these frequency combs convert a single-color input laser beam into a sequence of many additional colors that are evenly spaced and resemble a hair comb. A wide array of comb “teeth” coming available mean that innovative techniques to eliminate noise become possible, making combs a viable option for systems needing precise frequency references.
A simplified structure eliminates the specialized electronics and optics that are usually needed in between the devices, which the UCSB team posits reduces scale, power, and cost requirements while making the combs less susceptible to environmental and temperature disturbances.
“The UCSB team’s accomplishment could have broad reaching implications for a number of commercial and defense photonics applications – from navigation systems to optical clocks to coherent communications,” said Dr. Gordon Keeler, the DARPA program manager leading DODOS. “This work brings us one step closer to the creation of the next-generation of optical frequency control technology that isn’t restricted to a lab, but rather available for real-world use.”