Quantum Fisher information and nonclassical properties of a two-atom interacting with a radiation field in squeezed coherent states

In this paper, we consider the problem of the interaction between a two atoms and a radiation field in the squeezed coherent states with one- and two-photon processes. The analytic solution for the wavefunction of the whole system is used to describe various quantum measures. The article investigates the dynamics of entanglement between the squeezed coherent field with two atoms measured by quantum entropy. On the other side, the negativity is used to detect the atom–atom entanglement. The influence of the multiphoton transitions, the initial atomic state and intensity dependent function on the entanglement and Quantum Fisher Information (QFI) for the system under consideration is examined. Furthermore, we show how the QFI of the system states is affected and changed according to the main physical parameters. Finally, our results have reported some important phenomena such as entanglement sudden death and birth and its link with the dynamical behavior of the QFI.