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Updated: May 30, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Entanglement irreversibility from quantum discord and quantum deficit
Marcio F Cornelio1, Marcos C de Oliveira, Felipe F Fanchini
1Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, CEP 13083-859, Campinas, São Paulo, Brazil. mfc@ifi.unicamp.br
Physical Review Letters
|July 30, 2011
Summary
Quantum entanglement irreversibility is linked to quantum correlation measures like quantum discord. Researchers proved entanglement cannot be fully recovered using local operations for specific entangled states.
Area of Science:
- Quantum Information Science
- Quantum Computing
- Quantum Entanglement
Background:
- Entanglement is a key quantum resource, but its irreversibility under local operations is a significant challenge.
- Quantum correlation measures, such as quantum discord, offer new ways to quantify quantum correlations.
Purpose of the Study:
- To investigate the relationship between entanglement irreversibility and quantum correlation measures.
- To analyze the behavior of entanglement under local operations and classical communication (LOCC).
Main Methods:
- Relating entanglement irreversibility to quantum discord and one-way quantum deficit.
- Proving irreversibility for a generalized family of entangled states.
- Deriving analytical expressions for various entanglement and correlation measures.
Main Results:
- Entanglement of formation is consistently larger than coherent information.
- Entanglement cost is generally larger than coherent information.
- Irreversibility of entanglement is demonstrated for a specific class of entangled states.
Conclusions:
- Quantum discord and related measures provide insights into entanglement irreversibility.
- The derived analytical expressions offer a deeper understanding of quantum correlations in entangled states.
- This work contributes to the fundamental understanding of entanglement manipulation in quantum information processing.
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