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Time & frequency

Overview

Time and frequency activities at NIST include maintaining standards, providing official time to the U.S., and carrying out a broad program of research and service activities in time and frequency metrology.

The Research

Projects & Programs

Compact Cold Atom Instruments

Ongoing
Our research focuses on the development of novel sensing platforms using cold atomic gases and atomic beams. Laboratory-scale cold atom apparatuses provide some

Frequency Comb Spectroscopy

Ongoing
We use frequency combs based on ultrafast mode-locked lasers to perform precision spectroscopy in the near- and mid-infrared domains, for rapid, high

Additional Resources Links

What Is Time?

Philosophically, what is "time"? Even if we don’t completely understand what time is, we can precisely measure what time it is, thanks to the atomic clock, humankind’s most accurate measurement device. Atomic clocks have revolutionized navigation. Only time will tell us its future applications.

What is time?
What is time?

News

Keeping Time at NIST

Einstein is reported to have once said that time is what a clock measures. Some say that what we experience as time is really our experience of the phenomenon of entropy, the second law of thermodynamics. Entropy, loosely explained, is the tendency for things to become disorganized. Hot coffee always goes cold. It never reheats itself. Eggs don’t unscramble themselves. Your room gets messy and you

NIST-Designed Photonic Chip Transforms a Single Beam of Light Into Multiple Beams, Each With a Panoply of Different Properties

Jun Ye: A Timely Profile

NIST Lays Groundwork for Future Ultra-Precise Timing Links to Geosynchronous Satellites