NIST has developed a second-generation “quantum logic clock” using a single aluminum atom, making it the world’s most precise clock. The new clock is more than twice as precise as the previous mercury-based version, and would neither gain nor lose a second in about 3.7 billion years. The clock uses optical frequencies, which are 100,000 times higher than microwave frequencies used in current time standards.
The international definition of the second is based on the cesium atom, so no clock can be more accurate than cesium-based standards like NIST-F1. However, optical clocks like NIST’s quantum logic clock could someday lead to time standards more than 100 times as accurate as today’s microwave standards.
NIST scientists are working on five different types of experimental optical clocks, each based on different atoms. The construction of a second, independent version of the logic clock proves it can be replicated, making it one of the first optical clocks to achieve that distinction.
Keywords: Precision, Optical clocks, Aluminum, Frequency, Accuracy
