Entanglement of a Pair of Quantum Bits

@article{Hill1997EntanglementOA,
  title={Entanglement of a Pair of Quantum Bits},
  author={S H Hill and William K. Wootters},
  journal={Physical Review Letters},
  year={1997},
  volume={78},
  pages={5022-5025}
}
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. 

Figures from this paper

Entanglement of Formation of an Arbitrary State of Two Rebits

We consider entanglement for quantum states defined in vector spaces over the real numbers. Such real entanglement is different from entanglement in standard quantum mechanics over the complex

Operational measure of entanglement for pure states of bipartite systems

We show that the complete information about the amount of entanglement carried by a bipartite pure state of any dimension (qubits, qutrits, etc), is determined by a local quantity that can be

Note on Entanglement of an Arbitrary State of Two Qubits

It is shown that the norm of the polarization vector of the reduced density matrix can characterize the entanglement of two qubits and so it is defined as a simple measure of entanglement. It is then

Geometrical Representation of Entanglement of a Three-Qubit |W> State

In this paper we study the quantum entanglement properties of a tripartite system of qubits. We use the concept of two‐tangle and three‐tangle to understand the nature of entanglement of |W〉 and

Correlation between resource-generating capacities of quantum gates

We analyze the optimal basis for generating the maximum relative entropy of quantum coherence by an arbitrary gate on a two-qubit system. The optimal basis is not unique, and the high quantum

Entanglement of Formation

At least three distinct information-theoretic measures of quantum entanglement have been proposed in recent years. This paper highlights one of them, the entanglement of formation, as well as a

Entanglement of General Two-Qubit States in a Realistic Framework

New set of maximally entangled conditions are determined that provide the maximal amount of entanglement for certain values of the amplitudes of SCSs for the case of pure states.

Mixedness, Coherence and Entanglement in a Family of Three-Qubit States

We consider a family of states describing three-qubit systems. We derived formulas showing the relations between linear entropy and measures of coherence such as degree of coherence, first- and

Degree of Entanglement and Violation of Bell Inequality by Two-Spin-1/2 States

Bell inequality is violated by the quantum mechanical predictions made from an entangled state of the composite system. In this paper we examine this inequality and entanglement measures in the
...

References

SHOWING 1-8 OF 8 REFERENCES

Quantifying Entanglement

We have witnessed great advances in quantum information theory in recent years. There are two distinct directions in which progress is currently being made: quantum computation and error correction

Convex Functions

Trans

  • Am. Math. Soc. 135, 199 (1969); A. Uhlmann, Rep. Math. Phys. 9, 273 (1976); R. Jozsa, J. Mod. Optics41, 2315
  • 1994

Am. Math. Soc. Uhlmann, Rep. Math. Phys. Jozsa, J. Mod. Optics

  • Am. Math. Soc. Uhlmann, Rep. Math. Phys. Jozsa, J. Mod. Optics
  • 1969

Science

  • Science
  • 1995

Some alternatives to the definition we adopt , based on other criteria , are given in

  • Phys . Rev . Lett .
  • 1996

Phys. Rev. Lett

  • Phys. Rev. Lett
  • 1991

For a guide to some of the literature

  • Am. J. Phys
  • 1986