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Signatures for generalized macroscopic superpositions

E. G. Cavalcanti·M. D. Reid
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Abstract

We develop criteria sufficient to enable detection of macroscopic coherence where there are not just two macroscopically distinct outcomes for a pointer measurement, but rather a spread of outcomes over a macroscopic range. The criteria provide a means to distinguish a macroscopic quantum description from a microscopic one based on mixtures of microscopic superpositions of pointer-measurement eigenstates. The criteria are applied to Gaussian-squeezed and spin-entangled states.

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E. G. Cavalcanti, M. D. Reid. 2007-01-29. Signatures for generalized macroscopic superpositions. https://doi.org/10.1103/physrevlett.97.170405

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