Geometric quantum discord of a Jaynes–Cummings atom and an isolated atom
Wen-Chao Qiang, Lei Zhang, Huaping Zhang · Journal of Physics B Atomic Molecular and Optical Physics · 2015
We studied the geometric quantum discord of a quantum system consisting of a Jaynes–Cummings (JC) atom, a cavity and an isolated atom. The analytical expressions of the geometric quantum discord for two atoms, every atom with a cavity and the total system were obtained. We showed that the geometric quantum discord is not always zero when the entanglement falls to zero for a two-atom subsystem; the geometric measurement of the quantum discord of the total system developed periodically with a single frequency if the initial two-atom state was not entangled, otherwise, it oscillated with two or four frequencies according to whether the cavity was initially empty or not, respectively.