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Randolph Elmquist

Randolph E. Elmquist directs the Quantum Conductance project at the National Institute of Standards and Technology. Working for the past 32 years in the field of electrical and quantum metrology, he has contributed to the experimental design and measurement of the electronic Kilogram and calculable impedance standards for the determination of the von Klitzing constant and alpha, the unitless fine structure constant. He leads the development of cryogenic current comparator systems, the quantum Hall effect, and graphene electronic devices for metrology. He graduated with the PhD. degree in Physics from the University of Virginia and is a member of the American Physical Society and a senior member of the Institute of Electrical and Electronics Engineers.


AC and DC Quantized Hall Array Resistance Standards

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

Graphene quantum Hall effect devices for AC and DC resistance metrology

Mattias Kruskopf, Dinesh K. Patel, Chieh-I Liu, Albert F. Rigosi, Randolph E. Elmquist, Yicheng Wang, Stefan Bauer, Yefei Yin, Klaus Pierz, Eckard Pesel, Martin Goetz, Jurgen Schurr
The frequency dependence of the quantized Hall resistance at alternating current results from capacitive losses inside the sample as well as between the sample
Created June 4, 2019