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Entanglement in single particle systems

M. O. Terra Cunha·J. A. Dunningham·V. Vedral
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Abstract

We address some of the most commonly raised questions about entanglement, especially with regard to so-called occupation number entanglement. To answer unambiguously whether entanglement can exist in a one-atom delocalized state, we propose an experiment capable of showing violations of Bell's inequality using only this state and local operations. As a byproduct, this experiment suggests a means of creating an entangled state of two different chemical species. By comparison with a massless system, we argue that there should be no fundamental objection to such a superposition and its creation may be within reach of present technology.

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M. O. Terra Cunha, J. A. Dunningham, V. Vedral. 2006-06-19. Entanglement in single particle systems. https://arxiv.org/abs/quant-ph/0606149

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