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Physical Measurement Laboratory

Time and Frequency Division

The Time and Frequency Division maintains the standard for frequency and time interval for the United States, provides official time to the United States, and carries out a broad program of research and service activities in time and frequency metrology.

NIST on a chip

NIST-on-a-Chip in ADI
NIST-F1 Cesium Fountain Atomic Clock

NIST-F1 Cesium Fountain Atomic Clock
Yb Lattice Clock

Yb Lattice Clock

Popular Links

News and Updates

Events

2023 NIST Time and Frequency Seminar

Mon, Jul 10 - Wed, Jul 12 2023
NIST Time and Frequency Division's annual seminar covers clocks, oscillators, atomic frequency standards, rf and optical

Projects and Programs

CaPhoto

Calcium Thermal Beam Optical Clock

Ongoing
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
Compact Cold Atom Clock

Compact Cold Atom Instruments

Ongoing
The cooling of atoms to microkelvin temperatures using lasers is currently enabling a new generation of precision instruments that take advantage of the long

Awards

Dean of Staff awardee Judah Levine

2022 - Dean of Staff Award---Judah Levine

The Dean of Staff award honors the current employee with the longest tenure at NIST. The honoree receives a framed copy of an antique print of pioneering scientist Michael Faraday. A rare carbon print of this photo, now in NIST’s historical artifact collection, hung in the office of the first three NIST directors for four decades.

Patents

Ultrafast Electro-optic Laser

NIST Inventors
Scott Papp , Scott Diddams and David Carlson
patent description Our invention is for an ultrafast light source that produces femtosecond pulses with sub-cycle timing jitter using electro-optic switching of a continuous-wave (cw) laser. The apparatus is composed of the following key elements: 1) an electro-optic (EO) frequency comb, 2) a

Optical Reference Cavity

NIST Inventors
Franklyn Quinlan , Scott Diddams and Andrew Ludlow
Patent Description We have demonstrated an easy-to-manufacture 25-mm-long ultra-stable optical reference cavity geared toward transportable photonic microwave generation systems and mobile optical atomic clock applications. The cavity can be rigidly held in a way that is first-order insensitive to

METHODS AND APPARATUS FOR GENERATING MID-INFRARED FREQUENCY COMBS

NIST Inventors
Scott Diddams , Scott Papp , Abijith Kowligy and Alexander Lind
patent description We present a new approach to generating a coherent comb of infrared frequencies utilizing intra­ pulse difference frequency generation. The central claims of this invention are: A simple technique to generate few-cycle pulses derived from an amplified Er:fiber mode­ locked laser

Nobel Prize

2012 Nobel Prize in Physics to Dave Wineland of NIST Time and Frequency Division

Dave Wineland, of the Ion Storage Group, shares the 2012 Nobel Prize in Physics with Serge Haroche of France "for ground-breaking experimental methods that enable measuring and manipulation of individual quantum systems." Dave and his colleagues use these techniques for research in quantum information processing, quantum simulation, atomic clocks, and other areas.

More information about the Ion Storage Group can be found here.

For more information about the 2012 Nobel Prize in Physics, please see the Nobel Prize organization site.

Selected Publications

Contacts

Division Chief

Division Secretary