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Search Publications by: Alireza Panna (Fed)

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Displaying 1 - 25 of 30

Comparison of a 1 nF Capacitor with a 1 kO Resistor Using a Digital Impedance Bridge

March 27, 2024
Author(s)
Yicheng Wang, Stephan Schlamminger, Dean G. Jarrett, Alireza Panna, Andrew D. Koffman
This paper reports our effort to improve a digital impedance bridge. The limit of the bridge resolution and stability is less than 3 parts in 10^9 for the nominal 1:1 impedance comparison of two 100 pF capacitors. The type-A uncertainty for comparison of a

Graphene-Based Star-Mesh Resistance Networks

July 12, 2023
Author(s)
Dean G. Jarrett, Ching-Chen Yeh, Shamith Payagala, Alireza Panna, Yanfei Yang, Linli Meng, Swapnil Mhatre, Ngoc Thanh Mai Tran, Heather Hill, Dipanjan Saha, Randolph Elmquist, David B. Newell, Albert Rigosi

A Macroscopic Mass From Quantum Behavior In An Integrated Approach

December 10, 2022
Author(s)
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
Author(s)
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
Author(s)
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

Advanced Temperature-Control Chamber for Resistance Standards

April 10, 2020
Author(s)
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

Designing new structures in epitaxial graphene on SiC: transport and quantum effects

May 13, 2019
Author(s)
Randolph E. Elmquist, Hanbyul Jin, Mattias Kruskopf, Martina Marzano, Dinesh K. Patel, Alireza R. Panna, Albert F. Rigosi
When epitaxial graphene (EG) grows on hexagonal SiC(0001), chemical doping is produced by bonds at the epitaxial interface, or buffer layer. Robust quantum Hall effect (QHE) plateaus are observed at RK/2 = h/2e2, where RK is a constant of electrical