NIST researchers have made significant progress in developing a next-generation atomic clock using ytterbium atoms, which could be more stable and accurate than current microwave-based time standards. The experimental ytterbium clock, which operates at optical frequencies, is now about four times more accurate than previous versions and comparable in precision to NIST’s best cesium fountain clock.
The improved ytterbium clock gives the time standards community more options in the ongoing development and comparisons of next-generation clocks. NIST is developing five different versions of optical clocks, each using a different atom and offering different advantages. Optical clocks could potentially be up to 100 times more accurate than today’s microwave clocks.
The research supports development of technologies such as high data rate telecommunications and the Global Positioning System (GPS). Optical clocks are also providing record measurements of possible changes in the fundamental “constants” of nature, with huge implications for cosmology and tests of the laws of physics.
Keywords: atoms, clock, frequency, precision, standards
