The impact of the intrinsic decoherence on the dynamics of a system composed of two coupled qubits inside a two-mode cavity with a nondegenerate parametric amplifier is analytically investigated. High-order nonlinearity causes strong entanglement and mixedness, which are analyzed by using entropy, negativity, and log negativity. In the absence of intrinsic decoherence, it is found that qubit-qubit coupling improves the generation of population inversion, entanglement, and mixedness. The coupling acts as external decoherence in the presence of the intrinsic decoherence, and the quantum effects evolve monotonically to non-zero stationary values. The qubitqubit
entanglement is crucially dependent on the nonlinearity and the intrinsic decoherence. The stability of this entanglement is granted for small intrinsic decoherence.

In this paper, we study the dynamics of skew information correlations, beyond its
concurrence entanglement, between two coupled qubits interacting with containing
amplifier cavity fields. An analytical description has been obtained for the intrinsic
decoherence model when the cavity fields are initially in a superposition of generalized
Barut–Girardello coherent states. The concurrence and skew information quantifiers
present nonlocal correlations with different oscillatory behaviors, which can be controlled
by the two-qubit coupling and the initial cavity nonclassicality. The sudden
death–birth phenomenon is observed only in the concurrence entanglement behavior.
With the intrinsic decoherence, the stationary correlated two-qubit states can be
generated, which have different potential applications in quantum information. It is
found that the two-qubit coupling affects the generated nonlocal correlations (NLC)
as additional decoherence, reduces the generated nonlocal correlations, and accelerates
the stable correlations. The initial even-coherent nonclassicality enhances the nonlocal
correlations, which are more robust against the intrinsic decoherence.

This paper considers a qubit interacting time-dependently with parametric converter
two-mode cavity fields. The dynamics of quantum effects, population inversion and
quantum coherence, have been investigated when the cavity fields start from entangled coherent states. The qubit starts from a superposition state. We have examined the effects of the difference between the two-mode photon numbers, the qubit time-dependent location, and the initial qubit state on the dynamics of the generated quantum coherence. It is found that the dynamics of the population inversion, the entropies, and the negativity qubit-cavity entanglement can be controlled by the difference between the two-mode photon numbers, the qubit location parameter as well as the initial qubit state.

We have explored the non-locality of two qubits interacting time-dependently with a
nondegenerate parametric amplifier cavity fields in the presence of the Stark shift interaction term. The time-dependent two-qubit reduced density matrix is calculated numerically when the cavity fields are initially in two entangled coherent states. We investigate the non-locality via local Fisher information and negativity. It is shown that the generated non-locality depends on the time-dependent two-qubit location, the Stark shift interaction, the difference between the mean photon numbers of the two-cavity fields as well as the initial intensity coherent fields. The agreement of the generated correlations presented by the local Fisher information and the negativity depends on the
physical parameters. The Stark shift non-linearity and the difference between the mean photon numbers lead to reducing the generated correlations. The local Fisher information is more robust against the Stark shift interaction than the negativity.

We consider a time-dependent model that describes a qubit time-dependently interacting
with a cavity containing finite entangled pair coherent parametric converter fields. The
dynamics of some quantum phenomena, as phase space information, quantum entanglement, and squeezing, are explored by atomic Husimi function, atomic Wehrl entropy, variance, and entropy squeezing. The influences of the unitary qubit-cavity interaction, the difference between the two-mode photon numbers, the initial atomic coherence, and the time-dependent qubit location are investigated. It is found that the regularity, amplitudes, and frequency of the quantum phenomena can be controlled by the physical parameters. For the initial atomic pure state, the qubit-cavity entanglement, the qubit phase space information, and atomic squeezing can be generated strongly compared to those of the initial atomic mixed state. The time-dependent location parameters enhance the generated quantum phenomena, and their effect can be enhanced by the parameters of the two-mode photon numbers and the initial atomic coherence.

An analytical solution for a master equation describing the dynamics of a qubit interacting
with a nonlinear Kerr-like cavity through intensity-dependent coupling is established. A
superposition of squeezed coherent states is propped as the initial cavity field. The dynamics of the entangled qubit-cavity states are explored by negativity for the different deformed functions of the intensity-dependent coupling. We have examined the effects of the Kerr-like nonlinearity and the qubit-cavity detuning as well as the phase cavity damping on the generated entanglement. The intensity-dependent coupling increases the sensitivity of the generated entanglement to the phase-damping. The stability and the strength of the entanglement are controlled by the Kerr-like nonlinearity, the qubit-cavity detuning, and the initial cavity non-classicality. These physical parameters
enhance the robustness of the qubit-cavity entanglement against the cavity phase-damping. The high initial cavity non-classicality enhances the robustness of the qubit-cavity entanglement against
the phase-damping effect.

The sensitivity of local quantum Fisher
information and the Bures distance entanglement as
quantifiers of the non-classical correlations, is examined
for an atomic system interacting nonlinearly with
a single cavity field. The general behavior shows that,
the amount of the nonclassical correlation between the
atomic subsystems that are depicted by the local quantum
Fisher information is larger than that detected by Bures
distance entanglement. It is shown that, the long-lived
non-classical correlations between the atomic subsystems
is depicted in the presence of the intrinsic coherence
and enhanced by switching on the dipole-dipole
interaction. However, the upper bounds of these correlations
decreases if the field is initially prepared
in an even coherent state. Although the long-lived
the behavior of these correlations disappear at large values
of the mean photon numbers, but the maximum and minimum bounds of these correlations are enhanced.

In this paper, we explore the population inversion and entanglement dynamics
in a -qutrit interacting off-resonantly with a coherent cavity field through multi-quanta
processes based on the intrinsic decoherencemodel. Exact solutions of the decoherence model are obtained when the initial cavity field state is considered in two different states, coherent state and even super-position coherent state. The dynamics of the population inversion and the qutrit–cavity negativity are investigated under the effects of the initial cavity states, and the detuning as well as the decoherence. The energy transfer and entanglement induced by the qutrit–cavityinteraction can be controlled by these effects. The qutrit–cavitydetuning and the coherent intensity and the nonclassicality of the initial cavity field play an important role in improving the generated entanglement dynamics.

We introduce an analytical description of an open bimodal cavity containing a3-type three-level atom.We explore
the effect of the atom–cavity nonlinear interaction, the cavity dissipation, and the initial coherent intensity on the
dynamics of the nonclassical correlations for a cavity prepared initially in a superposition of nonlinear coherent
states. The nonlinear interaction generates a regular entanglement between the subsystems, and populates the
energy atomic states.We show that the collapse phenomenon is a good indicator of the generated quantum coherence.
The growth of the entropy is used to explore the generated entanglement (if the dissipation is absent) and
mixedness (in the presence of the dissipation). It is found that the generation and the robustness of the quantum
synchronization and the correlations between the subsystems are very sensitive to the dissipation, the superposition,
and the coherent intensity of the initial Barut–Girardello coherent states.