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Quantum teleportation via a W state

Jaewoo Joo·Young-Jai Park·Sangchul Oh·Jaewan Kim
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Abstract

We investigate two schemes of the quantum teleportation with a $W$ state, which belongs to a different class from a Greenberger-Horne-Zeilinger class. In the first scheme, the $W$ state is shared by three parties one of whom, called a sender, performs a Bell measurement. It is shown that quantum information of an unknown state is split between two parties and recovered with a certain probability. In the second scheme, a sender takes two particles of the $W$ state and performs positive operator valued measurements in two ways. For two schemes, we calculate the success probability and the average fidelity. We show that the average fidelity of the second scheme cannot exceed that of the first one.

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Jaewoo Joo, Young-Jai Park, Sangchul Oh, Jaewan Kim. 2003-08-13. Quantum teleportation via a W state. https://doi.org/10.1088/1367-2630%2F5%2F1%2F136

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