Scientists at JILA, a joint venture of NIST and the University of Colorado Boulder, have created the first “frequency comb” in the extreme ultraviolet (EUV) spectrum, enabling precise measurements of light at wavelengths below 100 nanometers. Frequency combs are tools that generate evenly spaced “teeth” of light, allowing precise frequency measurements.
The new EUV frequency comb, described in the journal Nature, represents a significant advancement in laser technology. It can be used for developing “nuclear clocks” based on atomic nucleus energy levels, studying plasmas, and searching for changes in fundamental constants of nature.
The comb was created using a high-power laser that generates infrared light pulses, which then produce EUV light through a process involving xenon gas. The resulting EUV comb has a mini-comb structure within each harmonic, providing unprecedented measurement precision.
This research was funded by DARPA, AFOSR, NIST, and NSF, and involved a collaboration with IMRA America Inc. The team hopes to extend the technology to create an X-ray frequency comb in the future.
Keywords: High-Precision, Frequency Combs, Laser Spectroscopy, Quantum Metrology, Atomic Clocks
