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arXiv · 1507.07679

Is macroscopic entanglement a typical trait of many-particle quantum states?

Malte C. Tichy·Chae-Yeun Park·Minsu Kang·Hyunseok Jeong·Klaus Mølmer
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Abstract

We elucidate the relationship between Schrödinger-cat-like macroscopicity and geometric entanglement, and argue that these quantities are not interchangeable. While both properties are lost due to decoherence, we show that macroscopicity is rare in uniform and in so-called random physical ensembles of pure quantum states, despite possibly large geometric entanglement. In contrast, permutation-symmetric pure states feature rather low geometric entanglement and strong and robust macroscopicity.

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Malte C. Tichy, Chae-Yeun Park, Minsu Kang, Hyunseok Jeong, Klaus Mølmer. 2015-07-28. Is macroscopic entanglement a typical trait of many-particle quantum states?. https://doi.org/10.1103/physreva.93.042314

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