Temporal evolution is studied for total entropy, the entropy difference and the sum of negative eigenvalues of the partially transposed
density matrix as quantitative entanglement measurements for JC model in a phase-damped cavity in the dispersive approximation. The
cavity field is assumed to be coupled to a reservoir with a phase-damping coupling. The case of a statistical mixture (SM) of coherent
states is considered as initial field state. The effects of cavity phase damping on the entanglement between the field and the atom are
studied.

In this paper, we investigate the temporal evolution of various measures of
degree of entanglement and total correlation of a single-mode light field
interacting with a two-level atom. The phase-damped cavity is taken into
account. The effects of phase damping on a temporal of partial entropies
for the atom and the field, total entropy, the entropy difference and the
sum of negative eigenvalues of the partially transposed density matrix as a
quantitative entanglement measure for the master equation in the dressed-state
approximation are taken into account.

In this paper, we investigate the temporal evolution of various measures of
degree of entanglement and total correlation of a single-mode light field
interacting with a two-level atom. The phase-damped cavity is taken into
account. The effects of phase damping on a temporal of partial entropies
for the atom and the field, total entropy, the entropy difference and the
sum of negative eigenvalues of the partially transposed density matrix as a
quantitative entanglement measure for the master equation in the dressed-state
approximation are taken into account.

An analytical method to calculate the sub-entropies and entanglement for the mixed state as an initial field is presented. Also, we investigate the effects of the atomic motion and the field-mode structure on sub-entropies and phase properties of the coherent superposition state and a statistical mixture of coherent states as initial field states taking into account different forms of the intensity-dependent coupling. The initial state, the atomic motion and the field-mode structure play important roles in the time evolution of the entropies, entanglement and phase properties.

An analytical method to calculate the sub-entropies and entanglement for the mixed state as an initial field is presented. Also, we investigate the effects of the atomic motion and the field-mode structure on sub-entropies and phase properties of the coherent superposition state and a statistical mixture of coherent states as initial field states taking into account different forms of the intensity-dependent coupling. The initial state, the atomic motion and the field-mode structure play important roles in the time evolution of the entropies, entanglement and phase properties.

In this paper, we study the time evolution of the entropies and the degree of entanglement
in the mixed state for a multi-quanta JC model taking into consideration Stark shift and
Kerr-like medium effect, we use a numerical method to investigate the time evolution
of the partial entropy of the atom and field subsystem. This is done in the framework of
themulti-quanta presses JCmodel with both the Stark shift and Kerr-likemedium effect
added. Furthermore, we examine the effect of the superposition states and a statistical
mixture of coherent states as an initial field on the entropies and entanglement. Our
results show that the setting of the initial state play an important role in the evolution
of the sub-entropies and entanglement.

In this paper, we study the time evolution of the entropies and the degree of entanglement
in the mixed state for a multi-quanta JC model taking into consideration Stark shift and
Kerr-like medium effect, we use a numerical method to investigate the time evolution
of the partial entropy of the atom and field subsystem. This is done in the framework of
themulti-quanta presses JCmodel with both the Stark shift and Kerr-likemedium effect
added. Furthermore, we examine the effect of the superposition states and a statistical
mixture of coherent states as an initial field on the entropies and entanglement. Our
results show that the setting of the initial state play an important role in the evolution
of the sub-entropies and entanglement.

We study how phase decoherence through intrinsic decoherence leads to growing entropy and a strong
degradation of the maximum generated entanglement as a measure of information content of ionic
state due to ion-laser interaction with a trapped ion. We calculate the partial entropy of the particle
(atom or trapped ion) and field subsystems as well as the total entropy. The total entropy is shown
to increase with time. Thus, the partial field or atomic entropy cannot be used as a direct measure of
the particle–field entanglement. We find that, at least qualitatively, the difference between the total
entropy and the sum of field and atom partial entropies can be used as an entanglement measure,
when compared with an established entanglement measure based on the negativity of the eigenvalues
of the partially transposed density matrix. We find a very strong sensitivity of the maximum generated
entanglement on the decoherence and the chosen intrinsic decoherence parameter