Classicality and anticlassicality measures of pure and mixed quantum states

@inproceedings{Dodonov2002ClassicalityAA,
title={Classicality and anticlassicality measures of pure and mixed quantum states},
author={Victor V. Dodonov and M. B. Ren{\'o}},
year={2002}
}

We introduce a simple measure of “classicality” of pure and mixed quantum states as a maximum value of the Hilbert– Schmidt “scalar products” between the renormalized statistical operators of the state concerned and all displaced thermal states. Choosing Fock states as the reference set, we introduce the measure of “anticlassicality”. Both measures are illustrated for the Fock, coherent phase, and generic mixed Gaussian states. Gaussian states are shown to be the closest to thermal states… CONTINUE READING