Epitaxial graphene for quantum resistance metrology
Mattias Kruskopf1,2, Randolph E Elmquist1
1National Institute of Standards and Technology, Fundamental Electrical Measurements, 100 Bureau Drive, Gaithersburg, MD, United States of America.
Metrologia
|April 19, 2019
Summary
Graphene quantised Hall resistance standards offer high precision measurements for the ohm. These advancements enable compact systems and show graphene
Area of Science:
- Materials Science
- Metrology
- Condensed Matter Physics
Background:
- Quantized Hall resistance (QHR) standards are crucial for electrical metrology.
- Current standards, often GaAs-based, require specialized and exclusive measurement conditions.
- There is a need for more accessible and precise resistance standards.
Purpose of the Study:
- To provide an overview of state-of-the-art graphene-based quantised Hall resistance (QHR) standards.
- To highlight the advantages of graphene over traditional materials for resistance metrology.
- To discuss the advancements in material growth and device fabrication for graphene QHR.
Main Methods:
- Development of large-area monolayer graphene growth techniques for uniform material properties.
- Optimization of device fabrication processes for graphene-based QHR devices.
- Precision measurements comparing graphene QHR standards with existing GaAs-based standards.
Main Results:
- Graphene-based QHR standards demonstrate high precision for the unit ohm.
- These standards operate under less exclusive measurement conditions compared to GaAs.
- Graphene exhibits advantages over GaAs in precision measurements of QHR.
- The research showcases significant achievements in graphene material and device engineering.
Conclusions:
- Graphene-based QHR standards represent a significant advancement in electrical metrology.
- They offer a pathway to more compact and accessible high-precision resistance measurement systems.
- The demonstrated performance validates graphene as a superior material for future resistance standards.
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