Quantifying Correlations via the Wigner-Yanase-Dyson Skew Information

In this paper, based on a discussion about the Wigner-Yanase-Dyson (WYD) skew information, the measure Fa,α(ρab) for correlations in terms of the WYD skew information is introduced and discussed. The following conclusions are obtained. For a classical-quantum state ρab, Fa,α(ρab)=0 if and only if ρab is a product state; Fa,α(ρab) is locally unitary invariant and convex on the set of states with the fixed marginal ρa; Fa,α(ρab) decreases under local random unitary operation on Hb; For a quantum-classical state ρab, Fa,α(ρab) decreases under local operation on Hb; Lastly, Fa,α(ρab) is computed for the pure states and the Bell-diagonal states, respectively.