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https://www.nist.gov/pml
Physical Measurement Laboratory
Developing and delivering trusted measurements to support national needs.
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News and Updates
Spotlight: Electromagnetic Proton Trap at the NIST Center for Neutron Research (NCNR)
Just how long do free-floating neutrons live on average? This electromagnetic proton trap at the NIST Center for Neutron Research (NCNR) is part of an effort to
Spotlight: Scientists Can Measure Laser Power Using HALO
By measuring laser power, scientists can help improve safety, quality control and performance over time.
Events
2090 Lab Metrology Info Hour – Railroad Track Master Scales and Weight Carts in Metrology Labs and Q&A
Thu, Feb 19 2026, 2:00 - 3:00pm EST
An overview of the current state of the railroad track scale infrastructure and its traceability will be discussed
2057 Mass Metrology Seminar
Mon, Mar 2 - Fri, Mar 13 2026
The two-week Mass Metrology Seminar is a "hands-on" seminar that incorporates approximately 30 percent lectures and 70
Awards
Quantum 100 - Jun Ye
Ye is “recognized for his curiosity and his hands-on approach to experimentation,” according to the Quantum 100 list. “He has built a world
2025 IEEE SA Emerging Technology Award - IEEE N42.59 Working Group
For the development of the first imaging performance standard for millimeter-wave systems for security screening of humans.
2025 AB Nexus Grant - Jun Ye
Principal Investigators: Lilliam Ambroggio, PhD (CU Anschutz) and Jun Ye, PhD (CU Boulder) Using quantum sensing and advanced laser
Press Coverage
Mars Time Ticks Faster Than Earth | Einstein Was Right
WION Podcast
Scientists have confirmed something straight out of science fiction — time on Mars moves differently than it does on Earth.
What Time Is It on Mars? NIST Physicists Have the Answer
Technology.org
Ask someone on Earth for the time and they can give you an exact answer, thanks to our planet’s intricate timekeeping system, built with atomic clocks, GPS
Patents
Laser Ultrastable Photonics with Integrated Nonlinearity for Extended Stability
NIST Inventors
Scott Papp Optical photonic integrated optical clocks on photonic integrated circuits are described. The optical clocks can provide the timing stability of atomic clocks at ultra-low size and power. The optical clocks are be fabricated using CMOS foundry fabrication processes.
Continuous-Wave Laser Source And Making A Continuous-Wave Laser Source
NIST Inventors
Scott Papp 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
Hyperpolarization Micro-Magnetic Resonance Imager for Three-Dimensional Imaging of a Biological Composition with Cellular Resolution
NIST Inventors
Stephen E. Russek and Karl Stupic A hyperpolarization micro-magnetic resonance imager for three-dimensional imaging of a biological composition with cellular resolution includes a hyperpolarizer source, hyperpolarizer transmission line, an NMR console, a nuclear magnetic resonance tuned circuit, an imaging cell, a magnet, a gradient
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
- (301) 975-4200
- (301) 975-3797
Associate Director for Measurement Services and Associate Director
- (301) 975-2223
- (301) 975-2304