Effect Of Atomic Decay Research Articles

Effect of atomic decay on purity, total correlations and entanglement of pure and mixed states

Abstract The atomic decay for a two level atom interacting with a single mode of electromagnetic field is considered. In particular for a coherent state or statistical mixture ( SM ) of two opposite coherent states as initial field states, the exact solution of the master equation is found. Effect of the atomic damping on the partial entropies of the atom or the field and the total entropy as a measures of the purity loss is investigated. The degree of entanglement by the negativity and the mutual information and the atomic coherence through the master equation is studied.

Quantum Superdense Coding Based on Coherent States in Cavity QED

A physical scheme for the implementation of quantum superdense coding has been proposed in Cavity QED. The detuned interaction between Λ-type three-level atoms and coherent fields constitute the main superdense coding process. The quantum superdense coding can be realized in an easier way, and the atoms are not excited during the whole process, so the effect of atomic decay is eliminated naturally.

Effects of atomic decay and dephasing on the formation of adiabatons in a Λ-configuration medium

The formation of the adiabatons solutions in a Λ-configuration atomic medium are numerically investigated in the presence of nonzero inter-level dephasing and inhomogeneous broadening. We show that stringent limits on the values of these widths are necessary for the formation of adiabatons. Details of the dynamics of the two pulses propagation are illustrated and compared for the different values of the parameters.

Dynamics of off-diagonal elements in regularly pumped micromasers with atomic decay

The dynamics of off-diagonal elements and phase diffusion processes in regular pumped micromasers with atomic decay are studied. The dependence of phase diffusion coefficients on time is also discussed. The effect of atomic decay on the phase diffusion coefficients is investigated. A formula to calculate the evolution of the off-diagonal elements, which is suitable for finite atomic lifetime is derived. When the field approaches its steady state, the evolution of the electric strength of the micromaser field becomes, to a very good approximation, an exponential decay independent of initial states, so the phase diffusion coefficients are constants. The calculation verifies the validity of the exponential decay assumption for a system approaching its steady state. We show that regularization of the pumping leads to a decrease of these coefficients. The phase diffusion coefficients as a function of interaction time have many peaks, which are due to the trapping states. The peaks decrease as atomic decay increases, because the trapping states are washed out by large atomic decay.