We consider the quantum correlations for a S=1/2 Ising-Heisenberg model of a symmetrical diamond chain. Firstly, we compare concurrence, quantum discord and 1-norm geometric quantum discord of an ideal diamond chain (J m = 0) in the absence of magnetic field. The results show no simple ordering relations between these quantum correlations, so that quantum discord may be smaller or larger than the 1-norm geometric quantum discord, which this observation contradict the previous result that provided by F. M. Paula [1]. Symmetrical behavior of quantum correlation versus ferromagnetic and anti-ferromagnetic coupling constant J is considerable. The effect of external magnetic field H and temperature-dependence is also considered. Furthermore, we study quantum discord and geometric measure of quantum discord with the effect of next nearest neighbor interaction between nodal Ising sites for a generalized diamond chain (J m = 0), and we observe coexistence of phases with different values of magnetic field for quantum correlations. Moreover, entanglement sudden death occurs while quantum discord, 1-norm geometric quantum discord and geometric quantum discord are immune from sudden death.

In this paper, we consider an entangled Ising-XYZ diamond chain structure. Quantum correlations for this model is investigated by using of quantum discord and trace distance discord. Quantum correlations is obtained for different values of the anisotropy parameter, magnetic field and temperature. By comparison between quantum correlations, we show trace distance discord is always larger than quantum discord. Finally, some novel effects, such as increasing the quantum correlations with temperature and constructive role of anisotropy parameter which may paly to the quantum correlations were observed.

So far, super quantum discord has been calculated explicitly only for Bell-diagonal states and expressions for more general quantum states are not known. In this paper, we derive explicit expressions for super quantum discord for a larger class of two-qubit states, namely, a 4-parameter family of two-qubit states. We observe that, weak measurements obtain more quantumness of correlations than strong measurements. As an application, the dynamic behavior of the super quantum discord under decoherence channel is investigated. We find that, the super quantum discord decrease monotonically as a function of the measurement strength parameter.

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So far, one-way information deficit (OWID) has been calculated explicitly only for Bell-diagonal states and the four-parameter family of X-states with additional assumptions and expressions for more general quantum states are not known. In this paper, we derive explicit expressions for OWID for a larger class of two-qubit states, namely, a five-parameter family of two-qubit states. The dynamic behavior of the OWID under decoherence channel is investigated and it is shown that the OWID is more robust against the decoherence than the entanglement.