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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Determination of continuous variable entanglement by purity measurements
Gerardo Adesso1, Alessio Serafini, Fabrizio Illuminati
1Dipartimento di Fisica E. R. Caianiello, Università di Salerno, INFM UdR di Salerno, INFN Sezione di Napoli, Gruppo Collegato di Salerno, Via S. Allende, 84081 Baronissi (SA), Italy.
Physical Review Letters
|March 5, 2004
Summary
We classify quantum entanglement in two-mode Gaussian states using mixedness. This provides a reliable experimental method to estimate continuous variable entanglement by measuring purity.
Area of Science:
- Quantum Information Science
- Quantum Optics
- Quantum Many-Body Systems
Background:
- Entanglement is a key resource in quantum information science.
- Two-mode Gaussian states are fundamental in continuous-variable quantum systems.
- Quantifying entanglement is crucial for quantum technologies.
Purpose of the Study:
- To classify entanglement in two-mode Gaussian states.
- To establish bounds for maximally and minimally entangled states.
- To enable experimental estimation of entanglement via purity measurements.
Main Methods:
- Classification based on total and partial mixedness.
- Derivation of exact bounds for entanglement.
- Utilizing global and marginal purities.
Main Results:
- Established a classification scheme for Gaussian state entanglement.
- Derived precise bounds for entanglement based on purity.
- Demonstrated a link between mixedness and entanglement degree.
Conclusions:
- Mixedness provides a robust measure for quantifying Gaussian entanglement.
- Purity measurements offer an experimentally accessible route to estimate entanglement.
- This work facilitates practical applications of continuous-variable entanglement.
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