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Physical Measurement Laboratory

Developing and delivering trusted measurements to support national needs.

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NIST Team Develops Technique to Stabilize the Phase of Weak Light Signals in Quantum Network
Four researchers pose standing around a large piece of scientific equipment covered with wiring and electronics.
NIST Ion Clock Sets New Record for Most Accurate Clock in the World

News and Updates

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Legal Metrology Meets the Digital Age

The days when a telephone was just a device to make phone calls are long gone. Nowadays, almost everybody has a smartphone with the capability to use it as a

Events

Advanced Mass Thumbnail

2053 Advanced Mass Seminar

Mon, Jul 28 - Thu, Aug 7 2025
The 9-day, hands-on Advanced Mass calibration seminar focuses on the comprehension and application of the advanced mass

Awards

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Press Coverage

Four researchers pose standing around a large piece of scientific equipment covered with wiring and electronics.

Ion clock claimed to be the most accurate ever

Lab + Life Scientist
Researchers at the US National Institute of Standards and Technology (NIST) have improved their atomic clock based on a trapped aluminium ion, to the extent

Patents

Continuous-Wave Laser Source And Making A Continuous-Wave Laser Source

NIST Inventors
Scott Papp and Jennifer Black
A method of designing a continuous-wave laser source having a target output wavelength and an input laser with a wavelength different from the target output wavelength includes the steps of receiving the target output wavelength, and subordinate properties of the laser source; determining a

Sound Pressure Metrology Instrument And Determining Sound Pressure From Index Of Refraction

NIST Inventors
Richard A. Allen , Randall P Wagner , Benjamin Reschovsky and Akobuije Chijioke
A sound pressure metrology instrument determines sound pressure from index of refraction and includes: a light source that produces source light; the optical cavity that: receives an acoustic field from the sound source; receives the source light from the light source; produces acoustic-modified

Contacts

PML Director and Deputy Director

Associate Director for Measurement Services and Associate Director

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