Nonclassical Correlations in a Three-Mode Continuous-Variable System

We investigate a standard measure of quantum discord for tripartite coherent states of the Greenberger–Horne–Zeilinger (GHZ) type. Furthermore, we check the monotonicity of a superquantum discord according to weak quantum measurements. We accomplish our study by manipulating the amount of quantum information lost during the perturbation of the quantum system and controlling the measurement strength. In addition, we calculate the entanglement of the system under study. Finally we compare the behavior of the three correlations.