Nonclassicality by Local Gaussian Unitary Operations for Gaussian States

A measure of nonclassicality [Formula: see text] in terms of local Gaussian unitary operations for bipartite Gaussian states is introduced. [Formula: see text] is a faithful quantum correlation measure for Gaussian states as product states have no such correlation and every non product Gaussian state contains it. For any bipartite Gaussian state [Formula: see text] , we always have [Formula: see text] , where the upper bound 1 is sharp. An explicit formula of [Formula: see text] for [Formula: see text]-mode Gaussian states and an estimate of [Formula: see text] for [Formula: see text]-mode Gaussian states are presented. A criterion of entanglement is established in terms of this correlation. The quantum correlation [Formula: see text] is also compared with entanglement, Gaussian discord and Gaussian geometric discord.