Time evolution of atomic population inverse of binomial photon field and negative binomial photon field interacting with two coupling atoms via intensity-dependent coupling
The time-evolution of atomic population inverse of binomial photon field and negative binomial photon field interacting with two coupling atoms via intensity-dependent coupling is investigated.The influences of interaction between atoms and the initial state of photon field on the atomic population inverse are discussed.
The time evolution of atomic occupancy for the system of squeezed vacuum field interacting with two coupling atoms via intensity-dependent coupling in two-photon transition are investigated. The influences of the atomic initial state, the interaction between atoms and the initial squeezed parameter of field on the atomic occupancy are discussed. The results show that periodical collapse-revival phenomenon of the time evolution of atomic occupancy appears, which is caused by the influence of the dipole-dipole interaction between atoms. The periods of the collapse-revival shortens till the collapse-revival disappears while increasing the interaction between atoms. The amplitude of oscillations decreases in increasing the initial squeezed parameter of field.
Abstract In this paper, we consider the interaction between two two-level atoms and a two-mode binomial field with a general intensity-dependent coupling regime. The outlined dynamical problem has explicit analytical solution, by which we can evaluate a few of its physical features of interest. To achieve the purpose of the paper, after choosing a particular nonlinearity function, we investigate the quantum statistics, atomic population inversion and at last the linear entropy of the atom-field system which is a good measure for the degree of entanglement. In detail, the effects of binomial field parameters, in addition to different initial atomic states on the temporal behavior of the mentioned quantities have been analyzed. The results show that, the values of binomial field parameters and the initial state of the two atoms influence on the nonclassical effects in the obtained states through which one can tune the nonclassicality criteria appropriately. Setting intensity-dependent coupling function equal to 1 reduces the results to the constant coupling case. By comparing the latter case with the nonlinear regime, we will observe that the nonlinearity disappears the pattern of collapse-revival phenomenon in the evolution of Mandel parameter and population inversion (which can be seen in the linear case with constant coupling), however, more typical collapse-revivals will be appeared for the cross-correlation function in the nonlinear case. Finally, in both linear and nonlinear regime, the entropy remains less than (but close to) 0.5. In other words the particular chosen nonlinearity does not critically affect on the entropy of the system.
By means of the quantum theory,the population inversion of two atoms in the system of two two-level atoms coupled to a light field in the Binomial Optical Field are investigated in the presence of phase decoherence in the multiphoton Tavis -Cumming Model.The influences of the phase decoherence coefficient,the parameters η of the binomial optical field,the maximum number of photons and the number of the transitional photons on the properties of the population inversion of two atoms have been discussed. The results show that the phase decoherence reduced the oscillation amplitude of the population inversion of two atoms and destroyed the atomic quantum characteristic.Changing the number of the transitional photons,evolved cycle and evolved intensity the population inversion of two atoms can be changed.The phenomena of collapse and revival disappear as photon number increase.When the binomial optical state changes from a coherent state to a Fock state,the oscillation frequency of the atomic population reduces gradually,the phenomena of collapse and revival vanishes gradually.