An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
A simple, compact alternative to the highest performing optical standards, the Ca clock uses a thermal beam of neutral atoms with one or two lasers to achieve
Every four years, the Committee on Data for Science and Technology (CODATA) issues recommended values of the fundamental physical constants. The values are
The cooling of atoms to microkelvin temperatures using lasers is currently enabling a new generation of precision instruments that take advantage of the long
We develop self-referenced mode-locked femtosecond lasers that function as the "gears" of optical clocks. The femtosecond laser clockwork is capable of phase
We have constructed portable frequency combs that have provided in situ calibration of astronomical spectrographs, to aid in the search for exo-planets.
The NIST Frequency Measurement and Analysis Service (FMAS) makes it easy to measure and calibrate any quartz, rubidium, cesium, or hydrogen maser frequency
Our research focuses on the use of trapped ions for precision measurements. In particular, we are interested in optical frequency metrology, which provides the
With micro-resonators (fabricated in house or by collaborators) we are developing microcombs, integrated reference cavities and low-noise laser sources. The
Optical cavities are essential elements of optical atomic clocks, as they serve to pre-stabilize the clock laser. Our Group is currently developing state-of-the
Since 1970, the National Institute of Standards and Technology (NIST) has awarded Precision Measurement Grants for significant research in the field of
The coherent control of quantum-mechanical systems holds promise for revolutionizing technologies including computing, simulation, secure communication and
The NIST Time Measurement and Analysis Service (TMAS) was designed to serve any organization that is required to maintain an accurate local time standard. The