Thermodynamic Metrology Group

Realizing Pressure, Temperature, and Length using Optical Interferometry

The group mission is to advance the state of the art in measurement of thermodynamic quantities. We have active efforts in optics, nano-photonics, and quantum-based metrology along with traditional precision measurements to advance U.S. industry. We collaborate nationally and internationally, and engage in metrology education and outreach.

Collaboration Opportunities

We invite collaboration on joint research, technology, and standards development projects. Want to work with us? Here’s how:

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Or contact a project PI directly to learn how to get involved.

Research Projects and Programs

Cold Core Technology Platform

Ongoing

We are building a cold-atom based sensor program that represents a new approach to metrology—to establish a set of chip-scale tools that enable real-world use

Fixed Point Development : Non-Metals

Ongoing

We are developing new fixed points and new maintenance systems for use with Standard Platinum Resistance Thermometers (SPRTs) below the triple point of water

Interferometry: INFER - Neutron Interferometric Microscopy of Small Forces and Hierarchical Structures

Ongoing

INFER is an NIST Innovations in Measurement Science (IMS) project that seeks to develop far field neutron interferometers to create multi-scale images (three

Photonic Dosimetry

Ongoing

As part of the NIST on a Chip program, the Photonic Dosimetry project is developing in-situ sub-micrometer ionizing-radiation dosimetry and calorimetry leading

Photonic Thermometry

Ongoing

Photonic Thermometry is a cutting-edge research program at NIST that aims to break the fundamental limitations of electrical resistance-based thermometry and

Platform for Realizing Integrated Molecule Experiments (PRIME)

Ongoing

PRIME (Platform for Realizing Integrated Molecule Experiments) aims to establish primary, quantum-based realizations for both the radiometric watt and kelvin

Quantum Pascal: Fixed Length Optical Cavity (FLOC) Pressure Standards

Ongoing

This project is fundamentally changing the method for realizing and disseminating the SI unit of pressure, the pascale (Pa). The underlying principal behind

Reliable Vaccine Storage

Ongoing

We study provider-level vaccine storage and temperature monitoring methods to develop best practice guidance for public health audiences.

Illustration of Thermal MagIC assembly with coils

Thermal MagIC: An SI-Traceable Method for 3D Thermal Magnetic Imaging and Control

Ongoing

We are developing a method to measure and regulate temperature throughout a three dimensional volume with Systeme International (SI)-traceable Thermal Magnetic

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Measurement Services Projects and Programs

Humidity

Ongoing

The NIST Thermodynamic Metrology Group maintains and develops national standards of humidity (in the range 1 nmol/mol to 0.6 mol/mol of water concentration)

Pressure

Ongoing

The NIST Thermodynamic Metrology Group (TMG) provides critical research into pressure measurement capabilities improving uncertainties in user facilities and

Thermometry

Ongoing

The NIST Thermodynamic Metrology Group maintains and develops national standards of temperature (in the range 0.65 K to 2011 K), and supports calibration of all

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Archive Projects and Programs

Acoustic Thermometry

Completed

By measuring the speed of sound in argon gas, we have determined thermodynamic temperature with unprecedented accuracy in the range 0 °C to 552 °C. Our results

Dynamic Pressure

Ongoing

Manufacturing processes by their very nature require a judicious, time-dependent use of pressure and temperature to transform a base material into a valuable

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News and Updates

Detangling Light-based Thermometers with Combs

August 29, 2023

Photonic thermometers , which measure temperature using light, have the potential to revolutionize temperature measurement by being faster, smaller, and more

Four researchers pose standing in a lab, smiling and wearing safety glasses, surrouded by wires and other electronics.

NIST Demonstrates a New ‘Primary Standard’ for Measuring Ultralow Pressures

August 10, 2023

Chip manufacturing, gravitational wave detectors and quantum computers could all benefit from better ways to measure a vacuum.

Hooked on Photonics? Math to the Rescue

September 28, 2022

Photonic thermometers – which measure temperature using light – have been around in optical fiber form for decades. These devices, called fiber Bragg gratings

A Primary Standard for Measuring Vacuum

July 15, 2022

A novel, quantum-based vacuum gauge system invented by researchers at the National Institute of Standards and Technology (NIST) has passed its first test to be

Publications

Opportunities for Fundamental Physics Research with Radioactive Molecules

September 18, 2023

Author(s)

Michail Athanasakis-Kaklamanakis, Mia Au, Jochen Ballof, Robert Berger, Anastasia Borschevsky, Alexander Breier, Dmitry Budker, Luke Caldwell, Christopher Charles, Vincenzo Cirigliano, Jordy de Vries, David DeMille, Jacek Jacek Dobaczewski, Ch. E. Dullmann, Ephraim Eliav, Ephraim Eliav, Jonathan Engel, Mingyu Fan, Victor Flambaum, Alyssa Gaiser, Ronald Garcia Ruiz, Konstantin Gaul, Thomas Geisen, Alexander Gottberg, Gerald Gwinner, Reinhard Heinke, Steven Hoekstra, Jason Holt, Nicholas Hutzler, Andrew Jayich, Stephan Malbrunot-Ettenauer, Takayuki Miyagi, Iain Moore, Petr Navratil, Witold Nazarewicz, Gerda Neyens, Eric Norrgard, Nicholas Nusgart, Lukas Pasteka, Roy Ready, Moritz Pascal Reiter, Mikael Reponen, Sebastian Rothe, Marianna Safronova, Andrea Shindler, Jaideep Singh, Leonid Skripnikov, Silviu-Marian Udrescu, Shane Wilkins

Radioactive molecules hold great promise for their discovery potential in diverse fields. The extreme nuclear properties of heavy, short-lived nuclei and the

Simulations of a frequency-chirped magneto-optical trap of MgF

September 8, 2023

Author(s)

Kayla Rodriguez, Nickolas Pilgram, Daniel Barker, Stephen Eckel, Eric Norrgard

We simulate the capture process of MgF molecules into a frequency-chirped molecular MOT. Our calculations show that by chirping the frequency, the MOT capture

Radiative Decay Rate and Branching Fractions of MgF

September 8, 2023

Author(s)

Eric Norrgard, Catherine Cooksey, Stephen Eckel, Nickolas Pilgram, Kayla Rodriguez, Howard W. Yoon, Yuly Andrea Chamorro Mena, Lukáš Pašteka, Anastasia Borschevsky

Here we report measured and calculated values of radiative decay rates and vibrational branching fractions for the A$^2\Pi$ state of MgF. The decay rate

Accurate measurement of the loss rate of cold atoms due to background gas collisions for the quantum-based cold atom vacuum standard

August 1, 2023

Author(s)

Daniel Barker, James A. Fedchak, Jacek Klos, Julia Scherschligt, Abrar Sheikh, Eite Tiesinga, Stephen Eckel

We present measurements of thermalized collisional rate coefficients for ultra-cold $^7$Li and $^87}$Rb colliding with room-temperature He, Ne, N$_2$, Ar, Kr

Patents (pending and active, not including provisional)

Triple Point Immersion Cell Article (pending), US20210072098A1. Tew & Nanninga. March 11, 2021

Deformometer for determining deformation of an optical cavity optic, US Patent 10,935,370. Ahmed, Douglass, Eckel, Egan, Hendricks, Stone. Mar 2, 2021

Deformometer for determining deformation of an optical cavity optic, US Patent 10,816,325. Ahmed, Douglass, Eckel, Hendricks, Stone. Oct 27, 2020

Photonic calorimeter and process for performing calorimetry, US Patent 10,782,421. Tosh, Ahmed, Fitzgerald, Klimov. Sep 22, 2020

Photonic dosimeter and process for performing dosimetry, US Patent 10,718,872. Tosh, Ahmed, Fitzgerald, Klimov. Jul 21, 2020

Uniaxial counter-propagating monolaser atom trap (pending), US20200120785A1. Eckel, Barker, Fedchak, Scherschligt, Norrgard, Klimov. Apr 16, 2020

High-resolution photonic thermometer article (pending), US20200103594A1. Klimov, Douglass, Ahmed. Apr 2, 2020

Photonic quantum dew point sensor (pending), US20200041431A1. Herman, Klimov, Purdy. Feb 10, 2020

Optofluidic Flow Meter, US Patent 10,151,681 B2. Ahmed & Cooksey. Dec 11, 2018

Optical temperature sensor and use of same, US Patent 9,726,553. Ahmed, Semanick, Taylor, Fan, Hafezi, Xu, Strouse. Aug 8, 2017

Tools and Instruments

Dew-point measurements for water in compressed gases

This project has been completed. The paper reporting the results is provided here . The NIST Thermodynamic Metrology Group (TMG) used its standard gravimetric

Leak Artifacts

Leak artifacts are calibrated in the range 1 x 10 -6 to 1 x 10 -13 mol/s (2 x 10 -2 to 2 x 10 -9 std. cm 3 /s at 0 °C). The calibration can be performed

Dynamic Humidity Measurements with the Hybrid Humidity Generator

The NIST Hybrid Humidity Generator (HHG) is NIST’s primary standard humidity generator and is used for calibration of all hygrometers sent to NIST. The HHG and

Piston gauges and pressure transducers

Piston gauges are used to calibrate customer piston gauges and pressure sensing devices. Piston gauges are calibrated via a direct comparison to another piston

Awards

2019 Fellow of the American Vacuum Society - James Fedchak

For pioneering work in the science and metrology of extreme high vacuum, and support of the stakeholder and scientific community.

2018 ANSI Next Generation Award - Michal Chojnacky

Recipients have been recognized for their significant contributions to national and international standardization activities, as well as an

2016 Robert D. Thompson Memorial Award - Dr. Christopher W. Meyer

For continuing contributions and dedication to the development of temperature measurement standards, including effective leadership of

2015 ASTM International Award of Merit - Dr. Weston L. Tew

For “exemplary leadership and contributions to the development of industry standards.”

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Press Coverage

Cold atoms used to create reliable pressure gauge for ultrahigh vacuum

Physics World

September 5, 2023

An effect that normally gets in the way of the magnetic trapping of atoms has been harnessed to create a new method for measuring pressure in ultrahigh vacuum

Scientists Have Developed a New Way to Measure ... Nothing

Popular Mechanics

September 4, 2023

Nothing is truly nothing. A bit paradoxical, sure, but it’s true. Anything that we refer to as “empty,” “devoid,” or “containing nothing” does, in fact, contain

Accurately Measuring Ultracold Trapped Atoms

VAT

May 25, 2023

The National Institute of Standards and Technology (NIST) developed a quantum-based vacuum gauge – a cold atom vacuum standard (CAVS) device – that eliminates

It’s pretty hard to measure nothing, but these engineers are getting close

PopSci+

August 8, 2022

The US still uses Cold War-era tech to calibrate vacuums for manufacturing. Is there a more precise (and fun) option out there?

Thermodynamic Metrology Group

Collaboration Opportunities

Research Projects and Programs

Measurement Services Projects and Programs

Archive Projects and Programs

News and Updates

Publications

Patents (pending and active, not including provisional)

Tools and Instruments

Awards

Press Coverage

Highlights

Related Links

Contacts

Group Leader

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