Smaller version Illustration of a conventional atomic fountain clock (left) next to NPL’s miniature atomic fountain clock.

Cesium beam clocks (left) and hydrogen masers are among the types of atomic clocks used by the National Institute of Standards and Technology (NIST) to determine official U.S. time. (J. Sherman, R.

On a campus in Boulder, Colorado, time just became a little more exact. Inside the National Institute of Standards and Technology, or NIST, a new atomic clock named NIST-F4 has begun to tick — not ...

Atomic clocks have long served as the benchmark for precise timekeeping by utilising the stable frequency of atomic transitions as a reference. Recent developments focus on harnessing coherent ...