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arXiv · 1404.7256

Detecting the degree of macroscopic quantumness using an overlap measurement

Hyunseok Jeong·Changsuk Noh·Seunglee Bae·Dimitris G. Angelakis·Timothy C. Ralph
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Abstract

We investigate how to experimentally detect a recently proposed measure to quantify macroscopic quantum superpositions [Phys. Rev. Lett. 106, 220401 (2011)], namely, "macroscopic quantumness" $\mathcal{I}$. Schemes based on overlap measurements for harmonic oscillator states and for qubit states are extensively investigated. Effects of detection inefficiency and coarse-graining are analyzed in order to assess feasibility of the schemes.

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Hyunseok Jeong, Changsuk Noh, Seunglee Bae, Dimitris G. Angelakis, Timothy C. Ralph. 2014-04-29. Detecting the degree of macroscopic quantumness using an overlap measurement. https://doi.org/10.1364/josab.31.003057

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