Beyond the rotating wave approximation. An intensity dependent nonlinear coupling model in two-level systems

An intensity dependent nonlinear coupling model of a two-level system interacting with a bimodal cavity field via two-photon transitions is investigated in a scenario where the rotating wave approximation is lifted. The model is numerically tested against simulations of normal squeezing variance and entropy squeezing factors based on the Heisenberg uncertainty principle and Shannon information theory derived from entangled states.