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Search Publications by: Chieh-I Liu (Assoc)

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Displaying 1 - 12 of 12

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

Graphene quantum Hall effect devices for AC and DC resistance metrology

August 28, 2020
Author(s)
Mattias Kruskopf, Dinesh K. Patel, Chieh-I Liu, Albert Rigosi, Randolph 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 and external parts. In this joint effort we report on ac quantum Hall measurements of a graphene

Quantum transport in graphene p-n junctions with Moire superlattice modulation

July 12, 2018
Author(s)
Jiuning Hu, Albert Rigosi, Ji Ung Lee, Hsin Y. Lee, Yanfei Yang, Chieh-I Liu, Randolph Elmquist, David B. Newell
This work presents simulations of quantum transport in graphene p-n junctions (pnJs) in which Moire superlattice potentials are incorporated to demonstrate the interplay of the effect of pnJs and Moire superlattice potentials. It is shown that the