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Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Anomalous Josephson current in junctions with spin polarizing quantum point contacts.
A A Reynoso1, Gonzalo Usaj, C A Balseiro
1Instituto Balseiro, Centro Atómico Bariloche, Río Negro, Argentina.
Physical Review Letters
|October 15, 2008
Summary
We found an anomalous supercurrent in Josephson junctions due to spin-orbit coupling and magnetic fields. This effect leads to current rectification, enabling new possibilities for superconducting electronics.
Area of Science:
- Condensed matter physics
- Quantum electronics
Background:
- Ballistic Josephson junctions are crucial for quantum electronics.
- Rashba spin-orbit coupling in two-dimensional electron gases influences spin properties.
- Quantum point contacts can act as spin filters in electronic circuits.
Purpose of the Study:
- To investigate the behavior of a ballistic Josephson junction with a quantum point contact in a two-dimensional electron gas featuring Rashba spin-orbit coupling.
- To explore the effects of an in-plane external magnetic field on the supercurrent properties of such a system.
Main Methods:
- Theoretical modeling of a Josephson junction incorporating a quantum point contact with Rashba spin-orbit coupling.
- Analysis of supercurrent behavior under an applied in-plane magnetic field.
Main Results:
- An anomalous supercurrent was observed even at zero phase difference between superconducting electrodes.
- The external magnetic field induced significant critical current asymmetries for different current flow directions.
- Supercurrent rectification effects were demonstrated.
Conclusions:
- The interplay of Rashba spin-orbit coupling and magnetic fields in Josephson junctions can lead to novel phenomena like anomalous supercurrents.
- The observed critical current asymmetries and rectification effects offer potential for spintronic and quantum computing applications.
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