In this article, we investigate the effects of phase damping on the temporal evolution of different
entanglement measurements and the amount of entanglement for the damped Jaynes–Cummings model. The
master equation is solved for any initial state in the two-level atom. Superpositions of two coherent states (
π/2or π out of phase) and their statistical mixture state are taken as initial states when a phase-damped cavity is
taken into account.
A two-mode cavity field coupled to a two-level atom and damped by the environment through a phasedamped
process is considered. For a chosen initial state, the effects of phase damping on the purity loss of
the global system and different bipartite partitions of the system (atom–two modes, mode–(atom–
mode)) through the tangles are considered. In particular, the effect of phase damping on the amount
of entanglement between atom and field is evaluated by the negativity.
atom via intensity-dependent coupling in the off-resonant case has been studied, where the
leakage of photon through the cavity is taken into account. The effects of cavity damping on
the coherence properties of the atom and the field are studied. The amount of entanglement is
compared with the total correlations. It is found that the atom–field system is inhibited from
going into a pure state in the off-resonant case.
CHIN.PHYS.LETT. Vol. 25, No. 7 (2008) 2492
H. A. Hessian∗, A. -B. A. Mohamed
Faculty of Science, Assiut University, Assiut, Egypt
The atomic decay for a two-level atom interacting with a single mode of electromagnetic field is considered. For a
chosen initial state, the exact solution of the master equation is found. Therefore, effect of the atomic damping on
entanglement (purity loss), degree of entanglement by the negativity, mutual information and atomic coherence
through the master equation are studied.
cavity. The effects of thermal photons ( ¯n = 0) on entanglement and coherence loss are investigated. It is found that the field is inhibited from going into a pure state and coherence is lost faster than in the case of zero temperature ( ¯n = 0)....
We investigate the entanglement in the interacting system of a single mode thermal field and a single qubit
with dissipation in the dispersive limit. The influence of initial temperature of thermal field and atoms on the
entanglement is then examined.
In this article, we study the effects of the atomic motion and the field-mode structure on
the entropies and entanglement of a generalized JC model. We have investigated different
forms of the intensity dependent function on the evolution of the entropies and entanglement
in the case of a coherent superposition state and a statistical mixture of coherent states as
the initial field states. We investigate the partial entropy of the atom and field subsystems
numerically. The setting of the initial state of the field-mode and the atomic motion plays
an important role in the evolution of the sub-entropies and entanglement.
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
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 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.