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Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
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Quantum Hall-based superconducting interference device
Andrew Seredinski1, Anne W Draelos1, Ethan G Arnault1
1Department of Physics, Duke University, Durham, NC 27708, USA.
Science Advances
|September 25, 2019
Summary
We demonstrate a graphene Josephson junction with efficient side gates. These gates control quantum Hall edge states, enabling localized supercurrents along the junction edges by modulating carrier density.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Electronics
Background:
- Josephson junctions are crucial for quantum electronics.
- Graphene offers unique electronic properties for novel device applications.
- Controlling quantum states in nanoscale devices is a key challenge.
Purpose of the Study:
- To investigate supercurrents in graphene Josephson junctions.
- To explore the role of side gates in modulating quantum Hall edge states.
- To study the behavior of localized supercurrents as a function of magnetic field and carrier density.
Main Methods:
- Fabrication of a graphene-based Josephson junction with integrated side gates.
- Utilizing side gates to independently modulate carrier density along the junction edges.
- Applying magnetic fields to induce quantum Hall edge states.
- Measuring supercurrents and conductance.
Main Results:
- Highly efficient side gates allow wide-range modulation of carrier density.
- Population of the next Landau level was achieved in magnetic fields (1-2 T).
- Observation of quantum Hall plateaus with conductance distinct from bulk filling factor.
- Demonstration of supercurrents localized along the edges when counter-propagating quantum Hall edge states are introduced.
Conclusions:
- Graphene Josephson junctions with side gates provide precise control over quantum edge states.
- Localized supercurrents can be generated and studied using this platform.
- The findings open avenues for advanced quantum electronic devices.
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