The DOI matches its Crossref record; 18 of the 18 references it cites were found in a registry or an index.
Entanglement of a Pair of Quantum Bits
Open accessAbstract
The ``entanglement of formation'' of a mixed state \ensuremath{\rho} of a bipartite quantum system can be defined as the minimum number of singlets needed to create an ensemble of pure states that represents \ensuremath{\rho}. We find an exact formula for the entanglement of formation for all mixed states of two qubits having no more than two nonzero eigenvalues, and we report evidence suggesting that the formula is valid for all states of this system.
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“The relation between the present and the original approach to concurrence [27,57] becomes apparent with the observation that the matrix τ defined here coincides with that introduced in Eq. (38)”
From Measures and dynamics of entangled states (2005) · cites this paper as [57]
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Cites
Quantum cryptography based on Bell’s theorem
Ekert, A. K. (1991) · Physical Review Letters · doi:10.1103/physrevlett.67.661 · Cited by 10,777
Mixed-state entanglement and quantum error correction
Bennett, C. H., DiVincenzo, D. P., Smolin, J. A., & Wootters, W. K. (1996) · Physical Review A · doi:10.1103/physreva.54.3824 · Cited by 5,272
Self-citationSeparability Criterion for Density Matrices
Peres, A. (1996) · Physical Review Letters · doi:10.1103/physrevlett.77.1413 · Cited by 5,191
Separability of mixed states: necessary and sufficient conditions
Horodecki, M., Horodecki, P., & Horodecki, R. (1996) · Physics Letters A · doi:10.1016/s0375-9601(96)00706-2 · Cited by 3,649
Concentrating partial entanglement by local operations
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Purification of Noisy Entanglement and Faithful Teleportation via Noisy Channels
Bennett, C. H., Brassard, G., Popescu, S., Schumacher, B., Smolin, J. A., & Wootters, W. K. (1996) · Physical Review Letters · doi:10.1103/physrevlett.76.722 · Cited by 2,961
Self-citationQuantum cryptography without Bell’s theorem
Bennett, C. H., Brassard, G., & Mermin, N. D. (1992) · Physical Review Letters · doi:10.1103/physrevlett.68.557 · Cited by 2,536
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Fidelity for Mixed Quantum States
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The ‘transition probability’ in the state space of a—algebra
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Quantum Privacy Amplification and the Security of Quantum Cryptography over Noisy Channels
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Information-theoretic aspects of inseparability of mixed states
Horodecki, R., & Horodecki, M. (1996) · Physical Review A · doi:10.1103/physreva.54.1838 · Cited by 576
Inseparable Two Spin-12Density Matrices Can Be Distilled to a Singlet Form
Horodecki, M., Horodecki, P., & Horodecki, R. (1997) · Physical Review Letters · doi:10.1103/physrevlett.78.574 · Cited by 402
Teleportation, Bell's inequalities and inseparability
Horodecki, R., Horodecki, M., & Horodecki, P. (1996) · Physics Letters A · doi:10.1016/0375-9601(96)00639-1 · Cited by 279
Collective tests for quantum nonlocality
Peres, A. (1996) · Physical Review A · doi:10.1103/physreva.54.2685 · Cited by 179
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Flagged first, then by citations
Research works printed but not linked: 1
- D. Bures, 1969, Trans. Am. Math. Soc., 135, 199
Cited by
Sorted by citations
Horodecki, R., Horodecki, P., Horodecki, M., & Horodecki, K. (2009) · Reviews of Modern Physics · doi:10.1103/revmodphys.81.865 · Cited by 10,118
Entanglement of Formation of an Arbitrary State of Two Qubits
Wootters, W. K. (1998) · Physical Review Letters · doi:10.1103/physrevlett.80.2245 · Cited by 8,290
Self-citationEntanglement in many-body systems
Amico, L., Fazio, R., Osterloh, A., & Vedral, V. (2008) · Reviews of Modern Physics · doi:10.1103/revmodphys.80.517 · Cited by 3,745
Coffman, V., Kundu, J., & Wootters, W. K. (2000) · Physical Review A · doi:10.1103/physreva.61.052306 · Cited by 2,619
Self-citationGühne, O., & Tóth, G. (2009) · Physics Reports · doi:10.1016/j.physrep.2009.02.004 · Cited by 2,401
Metadata
- Authors
- Hill, S., & Wootters, W. K.
- Affiliations
- Williams College (US)
- Venue
- Physical Review Letters
- Publisher
- American Physical Society (APS)
- Published
- 1997-06-30
- Volume
- 78
- Issue
- 26
- Pages
- 5022-5025
- ISSN
- 0031-9007 (ISSN-L)
- 1079-7114
- OpenAlex
- W2073781628
- Cited by
- 2,823
- References
- 18
- Citations by year
- 2026: 102 · 2025: 141 · 2024: 127 · 2023: 165 · 2022: 126 · 2021: 132 · 2020: 92 · 2019: 108 · 2018: 92 · 2017: 117 · 2016: 134 · 2015: 110 · 2014: 116 · 2013: 93 · 2012: 103
- FWCI
- 17.04
- Type
- journal article
- Language
- en
- Open access
- green
- arxiv.org
- Locations
- Physical Review Letters (publishedVersion)
- arXiv (Cornell University) (submittedVersion)
- CERN Document Server (European Organization for Nuclear Research) (submittedVersion)
- arXiv (Cornell University)
- Topics
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Information and Cryptography
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum Mechanics and Applications
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum many-body systems
- Keywords
- entanglement of formation, two-qubit systems, mixed states, singlets, bipartite quantum systems, exact formulas, quantum entanglement
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