# Quantifying coherence.

@article{Baumgratz2014QuantifyingC, title={Quantifying coherence.}, author={Tillmann Baumgratz and Marcus Cramer and Martin Bodo Plenio}, journal={Physical review letters}, year={2014}, volume={113 14}, pages={ 140401 } }

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…

## 1,324 Citations

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We present an alternative framework for quantifying the coherence of quantum channels, which contains three conditions: the faithfulness, nonincreasing under sets of all the incoherent superchannels…

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