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05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Tomography and entanglement in coupled Josephson junction qubits.
Niels Grønbech-Jensen1, Jeffrey E Marchese, Matteo Cirillo
1Department of Applied Science, University of California, Davis, California 95616, USA.
Physical Review Letters
|September 28, 2010
Summary
This study challenges the quantum entanglement interpretation of macroscopic quantum Josephson oscillators. A classical circuit model replicates experimental data, suggesting state tomography may not definitively prove quantum entanglement.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Electrical engineering
Background:
- Macroscopic quantum phenomena in Josephson junctions are actively researched.
- Previous studies claimed entanglement between two macroscopic quantum Josephson oscillators.
Purpose of the Study:
- To provide an alternative interpretation of experimental results.
- To investigate the classical behavior of Josephson oscillators.
Main Methods:
- Modeling the experimental system using a classical equivalent circuit.
- Simulating the circuit to generate a density matrix.
- Comparing simulation results with experimental data.
Main Results:
- The classical model successfully generated a density matrix similar to experimental findings.
- Classical analysis adequately explains the observed experimental results.
Conclusions:
- State tomography may not be an absolute determinant of quantum entanglement in this context.
- Classical physics can offer a compelling explanation for observed macroscopic quantum phenomena.
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