Narrow Results

We study the interaction between a moving four-level rubidium atom and a single mode cavity field in the presence of a nonlinear Kerr-like medium. We derive the basic equations of motion for the atomic system and show that it is exactly solvable in the rotating wave approximation. The momentum increment, the momentum diffusion and the quasi-probability distribution Q-function of this system are studied. We investigate numerically the influence of the Kerr medium on the evolution of the previous statistical properties in the exact resonant and nonresonant cases where the atom is initially in the ground state and the field is in a coherent state. It is found that the Kerr medium has an important effect on their evolutions. Finally, conclusions and discussion are given.

One of the most important challenges in theoretical physics is investigating the theory of quantum gravity. In this work, according to generalized uncertainty principle, we study the statistical aspects of diatomic gases. The generalized statistical quantities of the diatomic gases such as partition function, mean energy, entropy and specific heat at constant volume are obtained. Note that, in the limit $\alpha \to 0$, all of modified statistical characteristics of diatomic gases become the usual forms. Also, the effect of linear and quadratic GUP (LQGUP) on the partition function and mean energy of diatomic gases is investigated.