U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Physical Measurement Laboratory /Quantum Measurement Division

Fundamental Electrical Measurements Group

The Fundamental Electrical Measurements group provides the foundation of the nation's infrastructure through measurement services in the general areas of resistance and impedance and related quantities. As part of its mission, the group maintains an active research program in precision measurements based on fundamental constants and in the development of quantum electrical standards.

The FEM group uses physical laws, quantum invariants, and ultra-precision measurement techniques to create and refine a core set of experiments used as the US national standards for the ohm and farad. Based on the defining constants of the new SI, FEM researchers provide the fundamental traceability of the SI units through the exact values of quantum electrical constants. The group strives to improve the accessibility, reliability, precision, accuracy, and range of values that can be achieved and disseminated from each standard by advancing the state of the art in optical, mechanical, and, of course, electrical systems used in the realization of these units.

News and Updates

flexures animated gid

Mass Revolution: Kibble Balances for All

NIST is working on a big project in a small package. When you want to weigh something – anything – in the United States, whether it’s a truck full of cargo or a

Projects and Programs

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 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
metrology of the ohm team

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
A magnon, or spin wave, in a 1D chain. Credit: Sean Kelley/NIST

Optical Probes of 2D Magnetic Phenomena

Ongoing
The unique measurement capabilities developed in this Project enable diffraction-limited, optical spectra (both Raman and photoluminescence) to be collected and analyzed as a function of laser energy, polarization, temperature, magnetic field, and device parameters such as current load and back

Publications

Optimization of Wye-Δ-Type Quantum Hall Resistance Standard

Author(s)
Yanfei Yang, Dean G. Jarrett, Alireza Panna, Albert Rigosi, David B. Newell, Randolph Elmquist, Cheng Hsueh Yang, Ngoc Thanh Mai Tran
Theoretically wye-delta transformation can be used to realize ultra-high resistances up to PΩ. For graphene-based quantum Hall array resistance standards

Reproducible graphene synthesis by oxygen-free chemical vapour deposition

Author(s)
Jacob Amontree, Xingzhou Yan, Christopher DiMarco, Pierre Levesque, Tehseen Adel, Jordan Pack, Madisen Holbrook, Christian Cupo, Zhiying Wang, Dihao Sun, Adam Biacchi, Charlezetta Stokes, Kenji Watanabe, Takashi Taniguchi, Cory Dean, Angela R. Hight Walker, Katayun Barmak, Richard Martel, James Hone
The demonstration of large-scale graphene synthesis on Cu by chemical vapor deposition (CVD) has led to enormous interest worldwide over the past 14 years. The

Ring-exchange interaction effects on magnons in the Dirac magnet CoTiO3

Author(s)
Yufei Li, Thuc Mai, Mohammed Karaki, Evan Jasper, Kevin Garrity, Chase Lyon, Daniel Shaw, Timmothy DeLazzer, Adam Biacchi, Rebecca Dally, Daniel Heligman, Jared Gdanski, Tehseen Adel, Maria Munoz, Alex Giovannone, Amit Pawbake, Clément Faugeras, Jeffrey Simpson, Kate Ross, Nandini Trivedi, Yuanming Lu, Angela R. Hight Walker, Rolando Valdes Aguilar
In magnetically ordered materials with localized electrons, it has been known for a long time [1–3] that the fundamental interactions are due to exchange of

Awards

Jon Pratt Elected ASPE Fellow

Election to the ASPE College of Fellows is a highly prestigious honor that is intended to recognize and honor those exceptional members of

Press Coverage

Contacts

Group Leader