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Published on: August 2, 2019
Andreev probe of persistent current states in superconducting quantum circuits
V T Petrashov1, K G Chua, K M Marshall
1Department of Physics, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom.
Physical Review Letters
|October 26, 2005
Summary
Researchers measured persistent current quantum states in superconducting loops using Andreev interferometers. This new electrical resistance method offers a precise and rapid way to study quantum circuits.
Area of Science:
- Condensed matter physics
- Quantum mechanics
Background:
- Superconducting loops with Josephson junctions exhibit quantum states.
- Measuring these states is crucial for understanding quantum circuits.
Purpose of the Study:
- To measure persistent current quantum states in superconducting loops.
- To develop a precise and fast method for probing quantum circuits.
Main Methods:
- Utilized the sensitivity of Andreev interferometers to superconducting phase differences.
- Employed straightforward electrical resistance measurements for continuous readout.
- Constructed the energy spectrum of the quantum circuit.
Main Results:
- Successfully measured persistent current quantum states.
- Demonstrated a continuous readout of quantum states.
- Obtained the energy spectrum of the quantum circuit.
Conclusions:
- Andreev interferometers provide a highly sensitive probe for superconducting phase differences.
- Electrical resistance measurements offer a precise and fast alternative for quantum circuit analysis.
- The developed method is applicable to a wide range of superconducting circuits.
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