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Updated: Jul 16, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Increasing entanglement between Gaussian states by coherent photon subtraction
Alexei Ourjoumtsev1, Aurélien Dantan, Rosa Tualle-Brouri
1Laboratoire Charles Fabry de l'Institut d'Optique, CNRS UMR 8501, 91403 Orsay, France. alexei.ourjoumtsev@institutoptique.fr
Physical Review Letters
|March 16, 2007
Summary
Researchers enhanced quantum entanglement in Gaussian states using non-Gaussian operations. Coherent photon subtraction on light pulses created more complex, entangled states than the originals.
Area of Science:
- Quantum optics
- Quantum information science
Background:
- Gaussian entangled states are fundamental in quantum information.
- Non-Gaussian operations are key to advancing quantum technologies.
Purpose of the Study:
- To experimentally demonstrate the enhancement of entanglement in Gaussian states.
- To explore the use of non-Gaussian operations for entanglement distillation.
Main Methods:
- Generation of Gaussian quadrature-entangled light pulses using a nondegenerate parametric amplifier.
- Application of coherent single-photon subtraction as a non-Gaussian operation.
- Characterization of the resulting states' entanglement properties, including negativity and Wigner functions.
Main Results:
- Successfully increased entanglement in Gaussian states via non-Gaussian operations.
- Produced delocalized states with negative Wigner functions.
- Demonstrated entanglement negativity exceeding that of the initial Gaussian states.
Conclusions:
- Non-Gaussian operations, specifically photon subtraction, can effectively enhance entanglement.
- The experimental findings align well with theoretical predictions.
- This method offers a pathway for generating highly entangled non-Gaussian states.
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