Entanglement of a Pair of Quantum Bits
- 30 June 1997
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 78 (26), 5022-5025
- https://doi.org/10.1103/physrevlett.78.5022
Abstract
The “entanglement of formation” of a mixed state ρ of a bipartite quantum system can be defined as the minimum number of singlets needed to create an ensemble of pure states that represents ρ. 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.Other Versions
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