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Physical Measurement Laboratory

Quantum Measurement Division

Projects/Programs

Displaying 1 - 25 of 48
thermal converter

AC-DC Difference

Ongoing
The use of thermal converters for ac voltage metrology was introduced by Frank Hermach at NIST in 1952. The basic thermal converter is a thermoelement, consisting of a thermocouple positioned at the midpoint of a heater wire, enclosed in an evacuated bulb. The thermoelement senses the heat generated
joint quantum institute

Applications of Quantum Information

Ongoing
Human-scale physical phenomenon represent the emergent, complex behavior of simple, microscopic laws. In the past twenty years, improved understanding of these microscopic laws have suggested that typical large-scale systems — those used in modern day technology from transistors to mechanical

Atomic Spectroscopy Data Center

Ongoing
The Atomic Spectroscopic Data Center at NIST provides the most comprehensive collection of atomic spectroscopy data in the world. We monitor scientific literature and maintain bibliographic databases of all papers containing spectroscopic data. By evaluating and compiling data on energy levels
SI Base Units chart

Calibration of Force Transducers

Ongoing
The calibration report describes the relationship between the applied force and the measured deformation, either in electrical or mechanical units. A transducer can be calibrated using (1) a readout device furnished by the customer, in which case the transducer and the readout device are calibrated
traceability chain illustration

Calibration of Mass Standards

Ongoing
Redefinition of the Kilogram and Consensus Value of the Kilogram The unit of mass was redefined in May 2019 as part of a general revision to the International System of Units (SI). See SI Redefinition. The kilogram is now defined by the Planck constant. The International Prototype Kilogram (IPK) no

CODATA values of the fundamental physical constants

Ongoing
CODATA recommended values of the constants Database of references for data on the constants Publications: Reviews of Modern Physics ( 1998) ( 2002) ( 2006) ( 2010) ( 2014) Journal of Physical and Chemical Reference Data ( 1998) ( 2006) ( 2010) Resource Letter FC-1: The physics of fundamental
Anechoic-Chamber-400 X 324

Dynamic Mechanical Metrology: Acceleration, Force, and Acoustics

Ongoing
The Dynamic Mechanical Metrology Project develops standards and provides calibrations for SI-traceable acceleration, acoustical and dynamic force metrology. We develop improved reference standards and calibration techniques, sensor-embedded standards, calibration techniques for new technologies, and
Allen Goldstein

Electric Power Metrology and the Smart Grid

Ongoing
Major advancements in electric power generation, transmission, distribution and loads over the last 20 years have led to improvements, reliability, robustness, efficiency and energy security unlike anything from the proceeding 80 years. Combined, this power grid modernization has been called the
EBIT

Electron Beam Ion Trap (EBIT) Facility

Ongoing
The NIST EBIT is a table-top device which can produce matter in excess of ten million degrees Kelvin. At these temperatures, even the heaviest atoms shed most of their electrons. The highly charged ions which result are trapped by a configuration of electric and magnetic fields in an ultrahigh
A time series of a MoS2 flake exposed to increasing time under electrical stress shows the growth of defects denoted with red and yellow areas over time. S= source and D = drain electrode.

Evaluation of 2D and WBG Material Quality Toward Device Reliability

Ongoing
Two-dimensional (2D) and wide band gap (WBG) materials are some of the latest materials classes having the potential to be transformative because of their high carrier mobilities, tunable bandgap, and atomic-scale film thicknesses. Unexpected degradation and failure in device performance is often
Schematic of four-arm digital impedance bridge

Farad and Impedance Metrology

Ongoing
The primary facility for connecting the U.S. legal system of electrical units to the international system of units is the NIST calculable capacitor, with which the measurement of capacitance is effectively achieved through a measurement of length. Both the calculable capacitor and the chain of high
schematic diagram

Fundamental Constants in Nature

Ongoing
The Task Group on Fundamental Constants periodically publishes updated evaluations of the fundamental constants of physics and chemistry. These evaluations serve two purposes. First, they provide a self-consistent set of recommended values of the constants for all to use. Second, because they
Fourier transform spectrometer

High Resolution Atomic Spectroscopy

Ongoing
For many decades, the Atomic Spectroscopy Group at NIST has measured atomic data of vital use to astronomy and other fields using high resolution spectrometers that are found in few other places in the world. These include a 2-m path difference Fourier transfer (FT)spectrometer, a vacuum ultraviolet
guide to the SI covers

International System of Units (SI)

Ongoing
Members of the Fundamental Constants Data Center (FCDC) participate in meetings of the Consultative Committee for Units (CCU) which advises the International Committee for Weights and Measures on matters concerning the SI. The latest meeting of the CCU, held at the BIPM in June of 2013 was attended

Light-matter interactions in Semiconductor Nanostructures

Ongoing
We investigate the interaction of light with semiconductor-based nanostructures. We extend concepts of entanglement and coherence in atomic physics to our solid-state systems. Our devices are based on semiconductors, like GaAs. We use InAs quantum dots (QDs) in GaAs as artificial atoms; they have
rare earth ions in a host crystal

Memory

Ongoing
While photonic systems offer very robust qbits and are excellent for transporting quantum information between locations due to their minimal interactions with their environment, they are inconvenient for the storage of quantum information in one place. As a result there is significant interest in
A line drawing of a woman's head styled like a classical carved bust

METIS

Ongoing
A Metrology Exchange to Innovate in Semiconductors
QHARS

Metrology of the Ohm

Ongoing
The Metrology of the Ohm Project has been a leader in providing internationally consistent resistance standards that are readily available to support the scientific and industrial foundations of the U.S. economy. Through this very broad customer base, the activities of the project enable cost
weighing device

National Type Evaluation Program (NTEP)

Ongoing
NTEP requires industry to submit prototype weighing devices for evaluation to determine whether or not it meets the uncertainties which are related to tolerances associated with the intended final use in the marketplace. All devices sold in the United States for "legal for trade" purposes must pass
\\elwood

Newtonian constant of gravitation international consortium

Ongoing
The disagreement calls into question our ability to measure small forces on a laboratory scale. It also raises the question of whether the Newtonian force law is a complete description of gravity at these distances. An international consortium is being formed to address this problem. The
mass-in-vacuum precision mass comparator

NIST Mise en Pratique of the New Kilogram Definition

Ongoing
Realization Since the redefinition of the kilogram, the Mass and Force Group has been intricately involved with the NIST realization of mass via the Kibble balance. By maintaining traceability to the International Prototype Kilogram (IPK) via the 2019 calibration of NIST National Prototype K20, the