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Search Publications by: Shamith Payagala (Fed)

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Displaying 1 - 25 of 25

A Macroscopic Mass From Quantum Behavior In An Integrated Approach

December 10, 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, Darine El Haddad
The revision of the International System of Units (SI) on May 20th, 2019, has enabled new improved experiments to consolidate and simplify electrical and mechanical metrology currently underway. Historically within the SI, the definition of energy was only

Graphene Quantum Hall Effect Parallel Resistance Arrays

February 2, 2021
Alireza Panna, I Fan Hu, Mattias Kruskopf, Dinesh K. Patel, Dean G. Jarrett, Chieh-I Liu, Shamith Payagala, Dipanjan Saha, Albert Rigosi, David B. Newell, Chi-Te Liang, Randolph Elmquist
As first recognized in 2010, epitaxial graphene on SiC(0001) provides a platform for quantized Hall resistance (QHR) metrology unmatched by other 2D structures and materials. Here we report graphene parallel QHR arrays, with metrologically precise

AC and DC Quantized Hall Array Resistance Standards

August 28, 2020
Randolph E. Elmquist, Mattias Kruskopf, Dinesh K. Patel, I Fan Hu, Chieh-I Liu, Albert F. Rigosi, Alireza R. Panna, Shamith U. Payagala, Dean G. Jarrett
Quantized Hall array resistance standards (QHARS) span values from 100 (ohm) to 1 M(ohm) and demonstrate precision approaching that of single devices. This paper focuses on QHARS having values near 1 k(ohm) for increased sensitivity using room-temperature

Evaluation of an alternative null detector for adapted Wheatstone bridge

August 24, 2020
Shamith U. Payagala, Alana M. Dee, Dean G. Jarrett
The adapted Wheatstone bridge technique has been utilized at National Institute of Standards and Technology (NIST) and other National Metrology Institutes (NMIs) for high resistance measurements. In this work, we evaluate the suitability of a

Evaluation of NMIJ Traveling Dual Source Bridge Using NIST Adapted Wheatstone Bridge

August 24, 2020
Takehiko Oe, Shamith U. Payagala, Dean G. Jarrett, Nobu-Hisa Kaneko
DC high resistance measurement capability has been evaluated using a NMIJ traveling dual source bridge between NIST and NMIJ. The NMIJ bridge determines the resistance ratio by measuring the voltage ratio using a digital multimeter, 3458A. Based on the

Ohms Law Low-current Calibration System for Ionization Chambers

August 24, 2020
Dean G. Jarrett, Shamith U. Payagala, Ryan P. Fitzgerald, Denis E. Bergeron, Jeffrey T. Cessna, Charles J. Waduwarage Perera, Neil M. Zimmerman
A system for the calibration of electrometers that measure currents from ionization chambers is described. The calibration system uses a 1 GΩ standard resistor in series with a stable voltage source to generate calibration currents from 1 pA to 20 nA

Advanced Temperature-Control Chamber for Resistance Standards

April 10, 2020
Shamith Payagala, Alireza Panna, Albert Rigosi, Dean G. Jarrett
Calibration services for resistance metrology have continued to advance their capabilities and establish new and improved methods for maintaining standard resistors. Despite the high quality of these methods, there still exist inherent limitations to the

Comparison of Multiple Methods for Obtaining PO Resistances with Low Uncertainties

September 3, 2019
Kwang Min Yu, Dean G. Jarrett, Albert Rigosi, Shamith Payagala, Marlin E. Kraft
Capabilities for high resistance determinations are essential for calibration of currents below 1 pA, as typically requested in several applications, including semiconductor device characterization, single electron transport, and ion beam technologies

10 T? and 100 T? Resistance Comparison between NIST and AIST

July 9, 2018
Dean G. Jarrett, Takehiko Oe, Nobu Kaneko, Shamith U. Payagala
We report the results of a comparison of 10 TΩ and 100 TΩ high resistance standards between the National Institute of Standards and Technology (NIST) and the National Institute for Advanced Industrial Science and Technology (AIST). Three standard resistors

A Table-Top Graphene Quantized Hall Standard

July 8, 2018
Albert F. Rigosi, Alireza R. Panna, Shamith U. Payagala, George R. Jones Jr., Marlin E. Kraft, Mattias Kruskopf, Bi Y. Wu, Hsin Y. Lee, Yanfei Yang, Dean G. Jarrett, Randolph E. Elmquist, David B. Newell
We report the performance of a quantum standard based on epitaxial graphene maintained in a 5 T table-top cryocooler system. The ν = 2 resistance plateau, with a value of RK-90/2, is used to scale to 1 kΩ, allowing comparisons of the performance of a

Uncertainty of the Ohm Using Cryogenic and Non-Cryogenic Bridges

July 8, 2018
Alireza Panna, Marlin E. Kraft, Albert Rigosi, George R. Jones Jr., Shamith Payagala, Mattias Kruskopf, Dean G. Jarrett, Randolph Elmquist
We describe recent scaling measurements to decade resistance levels based on both cryogenic and non-cryogenic current comparator bridges. National measurement institutes and the International Bureau of Weights and Measures derive traceability for the SI