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Single observable concurrence measurement without simultaneous copies

A. Salles·F. de Melo·J. C. Retamal·R. L. de Matos Filho·N. Zagury
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Abstract

We present a protocol that allows us to obtain the concurrence of any two qubit pure state by performing a minimal and optimal tomography of one of the subsystems through measuring a single observable of an ancillary four dimensional qudit. An implementation for a system of trapped ions is also proposed, which can be achieved with present day experimental techniques.

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A. Salles, F. de Melo, J. C. Retamal, R. L. de Matos Filho, N. Zagury. 2006-11-01. Single observable concurrence measurement without simultaneous copies. https://doi.org/10.1103/physreva.74.060303

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