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Search Publications by: Alireza Panna (Fed)

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Displaying 26 - 50 of 62

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