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Updated: Jan 22, 2026
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Development of a 3D Graphene Electrode Dielectrophoretic Device
Published on: June 22, 2014
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Graphene Devices for Tabletop and High-Current Quantized Hall Resistance Standards
Albert F Rigosi1, Alireza R Panna1, Shamith U Payagala1
1Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 USA.
IEEE Transactions on Instrumentation and Measurement
|July 6, 2019
Summary
A new quantum Hall resistance standard uses epitaxial graphene in a tabletop system, eliminating the need for liquid helium. This breakthrough enables continuous, year-round access to precise resistance measurements, comparable to state-of-the-art devices.
Area of Science:
- Condensed Matter Physics
- Metrology
- Materials Science
Background:
- Quantum Hall effect provides a fundamental resistance standard.
- Traditional standards often rely on liquid helium, limiting accessibility and continuous operation.
- Epitaxial graphene offers a promising alternative material for quantum resistance standards.
Purpose of the Study:
- To evaluate the performance of an epitaxial graphene-based quantum Hall resistance standard.
- To demonstrate continuous, liquid-helium-free operation for resistance measurements.
- To assess resistance scaling methods using cryogenic current comparators.
Main Methods:
- Utilized a 5-T tabletop cryocooler system with epitaxial graphene.
- Employed binary cryogenic current comparator (BCCC) and direct current comparator (DCC) bridges for resistance scaling.
- Measured the ν = 2 quantum Hall plateau (RK/2).
Main Results:
- Achieved uncertainties comparable to state-of-the-art GaAs-based devices using BCCC.
- Demonstrated resistance scaling to 1 kΩ.
- Identified advantages and limitations of BCCC and DCC scaling paths.
Conclusions:
- Epitaxial graphene quantum Hall resistance standards offer a viable, accessible alternative to traditional methods.
- Continuous operation and reduced cryogenics requirements are significant advantages.
- Further research can optimize graphene standards for higher current applications.
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