Quantifying the Quantumness of an Ensemble of Quantum States

To quantify the quantumness of an ensemble of quantum states, in this article, we generalize the definition of fidelity and affinity between the states to the ensemble of states. Exploiting the notion of fidelity and affinity-based coherence quantifiers of a quantum state, we propose a quantumness quantifier for the ensemble of quantum states. It is shown that the proposed quantifier satisfies the necessary axioms of a bonafide measure of quantumness. Finally, we compute the quantumness of a few well-known ensembles.

Automated summary

In this article, a generalized definition of fidelity and affinity for an ensemble of quantum states is proposed. Based on these coherence quantifiers, a quantifier for the quantumness of the ensemble is developed. It is shown that this quantifier satisfies the necessary axioms of a legitimate measure of quantumness. The quantumness of several well-known ensembles is also computed.