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arXiv:1705.04341 · Physical review. D/Physical review. D.

All coherent field states entangle equally

Petar Simidzija, Eduardo Martín-Martínez

Published Jul 24, 2017• 21 citations
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Abstract

We analyze the interactions of particle detectors with coherent states of a free scalar field. We find that the eigenvalues of the postinteraction density matrices of i) a single detector, ii) two detectors, and iii) the partial transpose of the latter, are all independent of which coherent state the field was in. A consequence of these results is that a detector pair can harvest the same amount of entanglement from any coherent field state as from the vacuum.

DOI
10.1103/physrevd.96.025020

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