Measurable entanglement criterion for two qubits
Hoshang Heydari, Gunnar G. Bjork, Luis Lorenzo Sánchez-Soto
We propose a directly measurable criterion for the entanglement of two qubits. We compare the criterion with other criteria, and we find that for pure states, and some mixed states, it coincides with the state's concurrence. The measure can be obtained with a Bell-state analyzer and the ability to make general local unitary transformations. However, the procedure fails to measure the entanglement of a general mixed two-qubit state.
arXiv:quant-ph/0308091•Physical Review A•Dec 18, 2003•4 citations