Questions tagged [concurrence]
A quantification of quantum entanglement that also serves as a separability criterion. Concurrence equal to zero indicates an unentangled/separable state. A non-zero concurrence "quantifies" how far the states in question are from achieving separability.
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How to get to the formula for the entanglement of formation of two-qubit states?
An explicit formula for the entanglement of formation $E(\rho)$ for an arbitrary two-qubit state $\rho$ was given by Wooters in Entanglement of Formation of an Arbitrary State of Two Qubits. The ...
glS♦
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Why does $\sigma_y$ seem to have a special role in the two-qubit concurrence?
The concurrence of a two-qubit state $\rho$ can be written as
$$\mathcal C(\rho) = \max(0, \lambda_1-\lambda_2-\lambda_3-\lambda_4),$$
where $\lambda_i$ are the eigenvalues of $|\sqrt\rho\sqrt{\tilde\...
glS♦
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What is the relation between fidelity and concurrence for a two qubit maximally mixed state?
I am trying to understand the relation between Fidelity and Concurrence for a two qubit maximally mixed state. When I calculate the Fidelity and Concurrence, I observe that Concurrence is zero whereas ...
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What is the concurrence between A and BC?
I was studing about the monogamy.
Then I saw this phrase
$$C_{AB}^2 + C_{AC}^2 ≤ C_{A(BC)}^2$$
where $C_{AB}, C_{AC} $ are the concurrences between A and B and between A and C respectively, while $...
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