Tiny SParCS chip matches tabletop frequency combs in key tests

Researchers from JQI, NIST and partners demonstrated a chip-based optical frequency comb using a two-laser SParCS approach that matched bulky tabletop systems in stability and noise tests. A single chip handled multiple measurement tasks, a step toward portable atomic clocks and GPS-free navigation.

• SParCS uses two lasers as the comb's bookends instead of one
• The chip spans an octave, with top frequency about twice the lowest
• Optical frequency measured to within about 100,000 oscillations per second
• Lab stabilized over 10 times more microcombs in a year