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arXiv · 1704.06359

$N$ identical particles and one particle to entangle them all

Bruno Bellomo·Rosario Lo Franco·Giuseppe Compagno
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Abstract

In quantum information W states are a central class of multipartite entangled states because of their robustness against noise and use in many quantum processes. Their generation however remains a demanding task whose difficulty increases with the number of particles. We report a simple scalable conceptual scheme where a single particle in an ancilla mode works as entanglement catalyst of W state for other $N$ separated identical particles. A crucial novel aspect of the scheme, which exploits basically spatial indistinguishability, is its universality, being applicable without essential changes to both bosons and fermions. Our proposal represents a new paradigm within experimental preparation of many-particle entanglement based on quantum indistinguishability.

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Bruno Bellomo, Rosario Lo Franco, Giuseppe Compagno. 2017-08-22. $N$ identical particles and one particle to entangle them all. https://doi.org/10.1103/physreva.96.022319

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