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Updated: May 30, 2026
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Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Directional photoelectric current across the bilayer graphene junction
1Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208, USA.
Summary
Researchers demonstrate photon-assisted resonant chiral tunneling in bilayer graphene. An external field enables ideal transparency switching, paving the way for advanced optical electronic devices.
Area of Science:
- Condensed Matter Physics
- Quantum Optics
- Materials Science
Background:
- Chiral tunneling in materials exhibits unique electron-hole dynamics.
- Bilayer graphene offers tunable electronic properties.
- Controlling quantum transport phenomena is crucial for device applications.
Purpose of the Study:
- To investigate photon-assisted resonant chiral tunneling in bilayer graphene.
- To explore the effect of external electromagnetic fields on tunneling transparency.
- To demonstrate a novel mechanism for switching quantum transport properties.
Main Methods:
- Theoretical modeling of electron and hole behavior in a bilayer graphene barrier.
- Analysis of photon-assisted resonant tunneling under external electromagnetic fields.
- Investigation of the angular dependence of chiral tunneling.
Main Results:
- A directional photon-assisted resonant chiral tunneling phenomenon is identified.
- External electromagnetic fields can switch tunneling transparency from 0 to 1 without energy cost.
- The applied field modifies phase correlations, altering the angular dependence of chiral tunneling.
Conclusions:
- The proposed mechanism offers a novel way to control quantum transport in graphene.
- This phenomenon has potential applications in sub-millimeter and far-infrared optoelectronic devices.
- The findings open avenues for experimental verification and device implementation.
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