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arXiv:1307.0732

Can coarse measurements reveal macroscopic quantum effects?

Tian Wang, Roohollah Ghobadi, Sadegh Raeisi, Christoph Simon

Published Jul 2, 2013• 1 citation
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Abstract

It has recently been conjectured that detecting quantum effects such as superposition or entanglement for macroscopic systems always requires high measurement precision. Analyzing an apparent counter-example involving macroscopic coherent states and Kerr non-linearities, we find that while measurements with coarse outcomes can be sufficient, the phase control precision of the necessary non-linear operations has to increase with the size of the system. This suggests a refined conjecture that either the {\it outcome precision} or the {\it control precision} of the measurements has to increase with system size.

DOI
10.48550/arxiv.1307.0732

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