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Updated: Aug 12, 2026
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Compressibility of quantum mixed-state signals
1CREST Research Team for Interacting Carrier Electronics, School of Advanced Sciences, The Graduate University for Advanced Studies (SOKEN), Hayama, Kanagawa 240-0193, Japan.
Physical Review Letters
|July 20, 2001
Summary
Researchers developed a formula for optimal qubit compression in quantum information, achieving faithful compression of mixed states. The optimal rate equals the von Neumann entropy of the reduced ensemble after removing redundancy.
Area of Science:
- Quantum Information Theory
- Quantum Computing
- Quantum Communication
Background:
- Quantum information is encoded in ensembles of mixed states.
- Compressing quantum information is crucial for efficient quantum communication and storage.
- Understanding the structure of mixed states, including redundancy, is key to optimal compression.
Purpose of the Study:
- To derive a formula for the optimal number of qubits per message for faithful quantum information compression.
- To analyze the relationship between mixed state decomposition and compression rates.
- To establish the connection between the irreducible part of the Hilbert space and the ultimate compression limit.
Main Methods:
- Formulating a mathematical expression for optimal qubit allocation.
- Decomposing the Hilbert space associated with mixed states into redundant and irreducible components.
- Applying principles of quantum information theory to analyze compression fidelity.
Main Results:
- A formula is presented that determines the optimal number of qubits per message for asymptotically faithful compression.
- The decomposition of the Hilbert space reveals a redundant part that can be removed.
- The optimal compression rate is precisely determined by the von Neumann entropy of the reduced ensemble.
Conclusions:
- The study provides a precise method for compressing quantum information from mixed states.
- The von Neumann entropy quantifies the fundamental limit of quantum information compression.
- This work advances the understanding of quantum information theory and its practical applications in quantum computing and communication.
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