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Entanglement swapping between multi-qudit systems

Jan Bouda·Vladimir Buzek
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Abstract

We generalize the entanglement swapping scheme originally proposed for two pairs of qubits to an arbitrary number $q$ of systems composed from an arbitrary number $m_j$ of qudits. Each of the system is supposed to be prepared in a maximally entangled state of $m_j$ qudits, while different systems are not correlated at all. We show that when a set $\sum_{j=1}^q a_j$ particles (from each of the $q$ systems $a_j$ particles are measured) are subjected to a generalized Bell-type measurement, the resulting set of $\sum_{j=1}^q (m_j-a_j)$ particles will collapse into a maximally entangled state.

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Jan Bouda, Vladimir Buzek. 2002-01-19. Entanglement swapping between multi-qudit systems. https://doi.org/10.1088/0305-4470/34/20/304

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