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arXiv:cond-mat/0504068

Coherence phenomena

Vyacheslav I. Yukalov

Published Apr 4, 2005• 0 citations
arXivHTMLPDF

Abstract

The basic notions related to coherence phenomena are formulated. Two types of coherence are described, state coherence and transition coherence. Useful characteristics for quantifying coherence are defined, such as coherence functions, coherence radius, coherence length, and coherence time.
DOI
10.48550/arxiv.cond-mat/0504068

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We introduce a rigorous framework for the quantification of coherence and identify intuitive and easily computable measures of coherence. We achieve this by adopting the viewpoint of coherence as a physical resource. By determining defining conditions for measures of coherence we identify classes of functionals that satisfy these conditions and other, at first glance natural quantities, that do not qualify as coherence measures. We conclude with an outline of the questions that remain to be answered to complete the theory of coherence as a resource.
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