Metrology of the Ohm

Summary

Resistance standards traceable to NIST provide references for measurements of current at levels from 3000 A to below 20 fA and are used to support a wide variety of impedance, temperature, strain, and power measurements. This project develops the technology of quantum electrical measurements including the world's best high resistance standards and superconducting quantum interference device (SQUID) based scaling techniques. We have maintained close working relationships with researchers in other leading national institutes and successfully completed bilateral and key comparisons with the Bureau International des Poids et Measures (BIPM) and other National Metrology Institutes (NMI), serving as the pilot laboratory for several of these comparisons. This leadership has resulted in collaborative research on quantized Hall array resistance standards (QHARS) to 1 GΩ, cryogenic current comparators (CCCs) and improved resistance standards, development of low current and high current measurement techniques for reduced uncertainty of measurements based on resistance metrology, and staff being called upon to provide expert peer review of NMIs and evaluating other labs while performing resistance and current comparisons.

Description

1 GΩ star-mesh quantized Hall array resistance standards (QHARS), having 3 orders of magnitude fewer quantized Hall resistance elements than a largely-series QHARS.  100 MΩ, 1 GΩ, and 10 GΩ standard resistors were compared to the 1 GΩ QHARS and agreed within the combined standard uncertainties of values obtained by traditional scaling methods from 12.906 kΩ quantized Hall resistance standards.

Credit: NIST

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-effective electrical measurements at NIST and at more than 250 U.S. sites, leading to improved performance of products and services in a competitive world environment. The resistance calibration service brings a yearly income to NIST of several hundred thousands of dollars as well as supporting over a dozen other calibration areas. Project staff provide extensive customer contact and consultation on topics including low current measurements (for photodetectors, aerosol electrometers, ionizing radiation measurements) the characterization processes used with resistive shunts at very high current levels, and power loading measurements. Project scientists work in the U.S. and international communities, including support for comparisons at low, moderate, and high resistance levels and development of improved standards and techniques for better agreement between primary references.

The project collaborates in research on low current measurements, farad and impedance metrology, and active participation with the Quantum Conductance project that aims to develop quantum Hall resistance (QHR) devices from graphene. We provide ongoing support for the electronic kilogram experiment as well as pursuing scientific breakthroughs to maintain accurate local representations of the unit (conventional standards) and to develop improved quantum metrology, such as the introduction of resistive-winding cryogenic current comparators (CCCs) that enable stable SQUID operation with improved current sensitivity.

10 μΩ high-current standard resistor (current shunt) being calibrated at 3000 A.  A direct current comparator (DCC) bridge, with range extenders, high-current pneumatic reversing switch, and 3000 A current sources use a 100,000:1 ratio to calibrate the current shunt with a Thomas-Type 1 Ω standard resistor (shown in foreground).  The 10 μΩ current shunt was manufactured in 1907 by Otto Wolff Berlin and first calibrated by Physikalisch-Technische Reichsanstalt (PTR), as shown on the brass plate attached to the 10 μΩ current shunt (inset).

Credit: NIST

Major Accomplishments

• Gold Medal received from the U.S. Department of Commerce in 2025 (along with the Quantum Conductance Project, Quantum Waveform Metrology Project, Precision Electro-Mechanical Experiments Project) for leveraging quantum physics to develop the world's best standards for the ampere and kilogram, two of the seven fundamental measurement units of science.
• Dean Jarrett elevated to IEEE Fellow in 2025 for contributions to high resistance metrology and measurement standards and techniques.
• Successful fabrication and demonstration of star-mesh transformation devices with quantized resistance values up to 1 GΩ. This ground-breaking quantized Hall array resistance standard (QHARS) was used as a standard to calibrate 100 MΩ, 1 GΩ, and 10 GΩ standard resistors.
• Graphene quantum Hall resistance implemented for dissemination of the ohm. Gold Medal received from the U.S. Department of Commerce in 2018 (along with the Quantum Conductance project) for this pioneering work.
• Development of an innovative approach that links ionization chamber (IC) current measurements in radioactivity to the Quantum SI. Bronze Medal received from the U.S. Department of Commerce in 2020 (along with Radiation Physics and Nanoscale Device Characterization Divisions) for this innovative work.
• Piloted SIM Key Comparisons at 1 Ω, 1 MΩ, and 1 GΩ; developed analysis to link SIM NMIs to the international community
• Developed CCCs for scaling up to 1 GΩ with multiple links to the QHR standard; disseminating the measurement techniques to three other NMIs
• Developed standard resistors, transfer standards, and bridges for scaling up to 100 TΩ.
• Low current capability down to 20 fA traceable to quantum standards through high resistance and voltage.
• High current measurement techniques for current range extenders and resistance standards from 1 A to 3000 A.

REFERENCES of recent Major Accomplishments

Jason Underwood, Linsey Rodenbach, Ngoc Thanh Mai Tran, Alireza Panna, Zachary Barcikowski, Molly Andersen, Peng Zhang, Lixuan Tai, Randolph Elmquist, Dean G. Jarrett, David Goldhaber-Gordon, David B. Newell, and Albert Rigosi, “Single-cryostat integration of the quantum anomalous Hall and Josephson effects”, CPEM 2024 Conference Digest, Denver, CO, USA, July 6-11, 2024. DOI: 10.1109/CPEM61406.2024.10646010

Ngoc Thanh Mai Tran, Linsey K. Rodenbach, Jason M. Underwood, Alireza R. Panna, Zachary S. Barcikowski, Molly P. Andersen, Peng Zhang, Lixuan Tai, Kang L. Wang, Randolph E. Elmquist, Dean G. Jarrett, David B. Newell, David Goldhaber-Gordon, and Albert F. Rigosi, “Development of a Topological-Insulator-Based Quantum Resistance Standard”, CPEM 2024 Conference Digest, Denver, CO, USA, July 6-11, 2024. DOI: 10.1109/CPEM61406.2024.10646119

Yicheng Wang, Stephan Schlamminger, Dean G. Jarrett, Alireza Panna, and Andrew D. Koffman, “Comparison of a 1 nF Capacitor with a 1 kΩ Resistor Using a Digital Impedance Bridge”, CPEM 2024 Conference Digest, Denver, CO, USA, July 6-11, 2024. DOI: 10.1109/CPEM61406.2024.10646139

Yanfei Yang, Dean G. Jarrett, Alireza Panna, Albert Rigosi, David B. Newell, Randolph Elmquist, Cheng Hsueh Yang, and Ngoc Thanh Mai Tran, “Optimization of Wye-Delta-Type Quantum Hall Resistance Standard”, CPEM 2024 Conference Digest, Denver, CO, USA, July 6-11, 2024. DOI: 10.1109/CPEM61406.2024.10646005

Dean G. Jarrett, Albert Rigosi, Dominick Scaletta, Ngoc Thanh Mai Tran, Heather Hill, Alireza Panna, Cheng Hsueh Yang, Yanfei Yang, Randolph Elmquist, and David B. Newell, “Recursive Star-Mesh Transformations for Resistance Standards”, CPEM 2024 Conference Digest, Denver, CO, USA, July 6-11, 2024. DOI: 10.1109/CPEM61406.2024.10646049

Linsey K. Rodenbach, Ngoc Thanh Mai Tran, Jason M. Underwood, Alireza R. Panna, Molly P. Andersen, Zachary S. Barcikowski, Shamith U. Payagala, Peng Zhang, Lixuan Tai, Kang L. Wang, Randolph E. Elmquist, Dean G. Jarrett, David B. Newell, Albert F. Rigosi, David Goldhaber-Gordon, “Realization of the quantum ampere using the quantum anomalous Hall and Josephson effects”, WERB approved June 30, 2023, submitted to Nature Electronics., Aug. 1, 2023.  Resubmitted Dec.3, 2024. https://arxiv.org/abs/2308.00200

Dominick S. Scaletta, Swapnil M. Mhatre, Ngoc Thanh Mai Tran, Cheng Hsueh Yang, Heather M. Hill, Yanfei Yang, Linli Meng, Alireza R. Panna, Shamith U. Payagala, Randolph E. Elmquist, Dean G. Jarrett, David B. Newell, and Albert F. Rigosi, “Mathematical optimization of graphene-based quantized Hall arrays for recursive star-mesh transformations”, Applied Physics Letters, Vol.123, Issue 15, Oct. 9, 2023, https://doi.org/10.1063/5.0164735

Dipanjan Saha, Swapnil Mhatre, Ching-Chen Yeh, Alireza R. Panna, Shamith U. Payagala, Yanfei Yang, Dean G. Jarrett, David B. Newell, Albert F. Rigosi, and Randolph E. Elmquist, "Current Distribution Near Hot Spots in Graphene QHR Devices", IEEE Trans. on Instrum. Meas., Submitted Jan 2023.

Dean G. Jarrett, Ching-Chen Yeh, Shamith U. Payagala, Alireza R. Panna, Yanfei Yang, Linli Meng, Swapnil M. Mhatre, Ngoc Thanh Mai Tran, Heather M. Hill, Dipanjan Saha, Randolph E. Elmquist, David B. Newell, and Albert F. Rigosi, “Graphene-Based Star-Mesh Resistance Networks”, IEEE Trans. on Instrum. Meas., Vol. 72, June 28, 2023, DOI: 10.1109/TIM.2023.3290290

Yicheng Wang, Dean Jarrett, Andrew Koffman, and Stephan Schlamminger, “New Method for Determining Time Constant of Resistors”, Review of Scientific Instruments, 94, 034711 (2023); https://doi.org/10.1063/5.0143225, published 3/21/23

Yicheng Wang, Andreas Hafner, Dean Jarrett, Andrew Koffman, and Stephan Schlamminger, “A Two-Tone Digital Impedance Bridge”, CPEM 2022 Conference Digest, Wellington, New Zealand, Dec. 12-16, 2022.

Linli Meng, Alireza R. Panna, Swapnil Mhatre, Albert F. Rigosi, Shamith U. Payagala, Dipanjan Saha, Ngoc Thanh Mai Tran, Ching-Chen Yeh, Randolph Elmquist, Angela R. Hight Walker, Dean G. Jarrett, David B. Newell, and Yanfei Yang, “Quantitative characterization of epitaxial graphene for the application of quantum Hall resistance standard”, CPEM 2022 Conference Digest, Wellington, New Zealand, Dec. 12-16, 2022.

Randolph E. Elmquist, Dipanjan Saha, Swapnil Mhatre, Ching-Chen Yeh, Alireza R. Panna, Shamith U. Payagala, Albert F. Rigosi, and Dean G. Jarrett, “Characterizing Local Hot Spots in Graphene QHR Devices”, CPEM 2022 Conference Digest, Wellington, New Zealand, Dec. 12-16, 2022.

Dean G. Jarrett, Swapnil Mhatre, Shamith U. Payagala, Alireza R. Panna, Ching-Chen Yeh, Yanfei Yang, Ngoc Thanh Mai Tran, Dipanjan Saha, Albert F. Rigosi, David B. Newell, and Randolph E. Elmquist, “Graphene Quantized Hall Arrays as Wye-Delta Transfer Standards”, CPEM 2022 Conference Digest, Wellington, New Zealand, Dec. 12-16, 2022.

Shamith Payagala, Alireza Panna, Randolph Elmquist and Dean Jarrett, “Long-term Performance of Guarded Hamon Transfer Standards”, CPEM 2022 Conference Digest, Wellington, New Zealand, Dec. 12-16, 2022.

Alireza R. Panna,  Frank C. Seifert, I-Fan Hu, Lorenz H. Keck, Leon S. Chao, Shamith U. Payagala, Dean G. Jarrett, Chieh-I Liu, Dipanjan Saha, Randolph E. Elmquist, Stephan Schlamminger, Albert F. Rigosi, David B. Newell, and Darine Haddad, “QHR Standards for Direct Realization of a Macroscopic Mass”, CPEM 2022 Conference Digest, Wellington, New Zealand, Dec. 12-16, 2022.

Linsey K. Rodenbach, Alireza R. Panna, Shamith U. Payagala, Ilan T. Rosen, Molly P. Andersen, Joseph A. Hagmann, Peng Zhang, Lixuan Tai, Kang L. Wang, Dean G. Jarrett, Randolph E. Elmquist, Jason M. Underwood, David B. Newell, David Goldhaber-Gordon, and Albert F. Rigosi, “Assessment of Cr_0.12(Bi_0.26Sb_0.62)₂Te₃ as a Quantized Anomalous Hall Resistance Standard”, CPEM 2022 Conference Digest, Wellington, New Zealand, Dec. 12-16, 2022.

Frank Seifert, Alireza Panna, Lorenz Keck, Leon Chao, Shamith Payagala, Dean G. Jarrett, Dipanjan Saha, Randolph Elmquist, Stephan Schlamminger, Albert Rigosi, David B. Newell, and Darine El Haddad“, A Macroscopic Mass From Quantum Behavior In An Integrated Approach”, Communication Physics, 5, 321, Dec 10, 2022, https://doi.org/10.1038/s42005-022-01088-7

Albert F. Rigosi, Mattias Kruskopf, Alireza R. Panna, Shamith U. Payagala, Dean G. Jarrett, Randolph E. Elmquist, and David B. Newell, “Progress of Quantum Hall Research for Disseminating the Redefined SI”, chapter in Handbook of Metrology and Applications, November 18, 2022. https://doi.org/10.1007/978-981-99-2074-7

T. Oe, S. Payagala, A. R. Panna, S. Takada, N.-H. Kaneko, and D. G. Jarrett, “Precise high resistance comparison between the NMIJ Traveling Dual Source Bridge and the NIST Adapted Wheatstone Bridge”, Metrologia, published October 28, 2022, https://doi.org/10.1088/1681-7575/ac9681

Linsey Rodenbach, Alireza Panna, Shamith Payagala, Ilan Rosen, Peng Zhang, Lixuan Tai, Kang Wang, Dean G. Jarrett, Randolph Elmquist, David B. Newell, David Goldhaber-Gordon, and Albert Rigosi, “Quantum Anomalous Hall Resistance Standards”, Physical Review Applied, 2 Sept 2022, https://doi.org/10.1103/PhysRevApplied.18.034008.