NIST researchers have developed a new method to boost the stability of microwave signals by a factor of 100, using advanced atomic clocks, light detectors, and frequency combs. This breakthrough could enable more accurate timekeeping, improved navigation, reliable communications, and higher-resolution imaging for radar and astronomy.
The team used NIST’s ytterbium lattice clocks, which operate at optical frequencies, to generate light pulses. These pulses were then converted into microwave signals using frequency combs and advanced photodiodes. The resulting microwave signal tracked the clocks’ ticking with an error of just one part in a quintillion.
This level of stability is on par with optical clocks and 100 times more stable than current microwave sources. The researchers believe some components of the system, like the frequency combs and detectors, could be implemented in field applications now, while work continues on transferring optical clocks to mobile platforms.
The improved microwave signals could have widespread applications, including future calibration of electronic clocks, more reliable wireless communications, and enhanced radar sensitivity for detecting slow-moving objects. The research was supported in part by the Defense Advanced Research Projects Agency.
Keywords: frequency, stability, microwave, optical, clocks
