  Recently, the basic concept of quantum coherence (or superposition) has
gained a lot of renewed attention, after Baumgratz et al. [PRL 113:140401
(2014)], following \AA{}berg [arXiv:quant-ph/0612146], have proposed a resource
theoretic approach to quantify it. This has resulted in a large number of
papers and preprints exploring various coherence monotones, and debating
possible forms for the resource theory. Here we take the view that the
operational foundation of coherence in a state, be it quantum or otherwise wave
mechanical, lies in the observation of interference effects.
  Our approach here is to consider an idealised multi-path interferometer, with
a suitable detector, in such a way that the visibility of the interference
pattern provides a quantitative expression of the amount of coherence in a
given probe state. We present a general framework of deriving coherence
measures from visibility, and demonstrate it by analysing several concrete
visibility parameters, recovering some known coherence measures and obtaining
some new ones.
