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Updated: May 16, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Robust-fidelity atom-photon entangling gates in the weak-coupling regime
Ying Li1, Leandro Aolita, Darrick E Chang
1Centre for Quantum Technologies, National University of Singapore, Singapore 117543, Singapore.
Physical Review Letters
|December 11, 2012
Summary
We developed a new method for entangling photonic qubits using photon scattering. This technique offers built-in error correction, improving quantum information applications.
Area of Science:
- Quantum optics
- Quantum information science
- Atomic physics
Background:
- Quantum information processing relies on high-fidelity quantum gates.
- Efficient atom-photon interfaces are crucial for quantum networks and computation.
- Existing methods often struggle with error correction and fidelity in weak-coupling regimes.
Purpose of the Study:
- To present a novel, simple entangling principle for photonic qubits.
- To introduce a scheme with inherent error correction capabilities.
- To enable high-fidelity quantum gates suitable for quantum information applications.
Main Methods:
- Utilizing the scattering of photons off single emitters in one-dimensional waveguides.
- Applying the scheme to polarization- or time bin-encoded photonic qubits.
- Implementing a filtering mechanism for error correction.
Main Results:
- Demonstrated a principle for high-fidelity maximally entangling gates, even in the weak-coupling regime.
- Showcased a filtering mechanism that converts errors into heralded losses, not infidelities.
- Established a method suitable for quantum information applications and atom-photon interfaces.
Conclusions:
- The proposed scheme provides a robust method for generating entangled photonic qubits.
- The built-in error correction significantly enhances the applicability in quantum information.
- This work contributes to the development of quantum computing and quantum communication technologies.
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