Narrow Results

In this paper, we study the quantum entanglement of three two-level atoms under the action of Fock state of a single-mode quantized radiation field. Milburn model is considered. Concurrence of the two atoms is given explicitly. As is expected, because of the intrinsic decoherence, Concurrence comes to a stationary value. A rule is summarized between this value and entanglement sudden death. As for the potential measurement of multi-particle entanglement, spin squeezing parameter is calculated.

We study the quantum speed limit (QSL) time of the two-qubit XYZ spin chain model with the influence of intrinsic decoherence. We show that the intrinsic decoherence can suppress the evolution of this system, no matter what initial states the two qubits start from. The investigation of entanglement reveals that quantum correlation is the physical reason for the acceleration of the system. In addition, we also demonstrate that for different initial states, external magnetic field may have opposite influence on QSL time and it mainly derives from the inhibition of entanglement as magnetic field increases.

In this paper, we explore the dynamics of quantum correlations in an isolated physical quantum dot under the influence of intrinsic decoherence (ID). We characterize quantum correlations in the quantum dot system using Concurrence to capture the amount of entanglement, and we use Trace Distance Discord (TDD) and Local Quantum Uncertainty (LQU) to measure nonclassical correlations. Likewise, we investigate the effect of ID on the temporal evolution of these quantifiers. In particular, the behavior of the two discord-like quantifiers in terms of the system parameters and the ID rate is investigated and analyzed in detail. We found that TDD and LQU behave similarly for different parameters characterizing the considered system and that TDD is more resistant than Concurrence and LQU against the ID effects. Our results also show that the robustness of quantum correlations can be modulated by adjusting the ID rate, quantum dot physical properties and initial conditions.

A system of three-coupled quantized fields is studied under the intrinsic decoherence scheme given by the Milburn equation. Taking the closed analytical form of this relation, without second-order approximation, we arrive at an explicit analytical solution for the wavefunction dynamics. We show the decaying behavior in the number of modes of each quantized field for suitable initial conditions. One of the modes goes coherently driven, and the others are vacuum states. We discuss the redistribution of the excitations.

Intrinsic decoherence in the thermodynamic limit is shown for a large class of many-body quantum systems in the unitary evolution in NMR and cavity QED. The effect largely depends on the inability of the system to recover the phases. Gaussian decaying in time of the fidelity is proved for spin systems and radiation-matter interaction.

This research delves into the influence of intrinsic decoherence on the behavior of quantum correlations and coherence between two interacting qubits in a graphene-based system. To evaluate the amount of nonclassical correlations in the system, we employ local quantum uncertainty (LQU), and to assess quantum coherence we use the relative entropy of coherence $(C_r)$ and $l_1$-norm $(C_{l_1})$. We assume that the system is initially prepared in an extended-Werner-like (EWL) state, and we investigate how these quantifiers evolve over time and examine their sensitivity to various graphene layer system parameters, mixture parameter of the initial state and the intrinsic decoherence rate. Our results indicate that by adjusting the wave number operators, decreasing the intrinsic decoherence rate, and increasing the initial state mixing parameter, it is possible to enhance both quantum correlations and coherence within the two-dimensional honeycomb lattice system. In addition, we found that quantum coherence is more resilient to intrinsic decoherence than LQU, moreover, the $l_1$-norm is more robust than the relative entropy of coherence.

Considering the dipole–dipole coupling intensity between two atoms and the field in the Fock state, the entanglement dynamics between two atoms that are initially entangled in the Tavis–Cummings model with intrinsic decoherence have been investigated. The two-atom entanglement appears with periodicity without considering intrinsic decoherence. However, the intrinsic decoherence causes the decay of entanglement between two atoms, with the decrease of the intrinsic decoherence coefficient, the entanglement will quickly become a constant value, which is affected by the two-atom initial state, the dipole–dipole coupling intensity and the field in the Fock state. Meanwhile, the two-atom quantum state will stay forever in the maximal entangled state when the initial state is proper, even in the presence of intrinsic decoherence. Furthermore, the two atoms can generate maximal entangled state even if they are initially separated by adjusting the dipole–dipole interaction, the strong coupling can improve the value of entanglement.

We investigate the effect of the Dzyaloshinskii–Moriya anisotropic antisymmetric interaction on entanglement in a three-qubit Ising model with intrinsic decoherence. The entanglement of the nearest and the next-nearest neighbor qubit is calculated. The results show that, taking into account the intrinsic decoherence, when the qubits are initially in the maximal entangled state, the concurrence of the system decreases with the increasing Dzyaloshinskii–Moriya interaction following the evolution of the time t. When the qubits are initially in the disentangled state, the destructive effect of intrinsic decoherence on entanglement can be moderated by the Dzyaloshinskii–Moriya interaction, the concurrence increases with the increasing Dzyaloshinskii–Moriya interaction following the evolution of the time t.

We study qutrit teleportation and its fidelity in the presence and absence of intrinsic decoherence through a qutrit channel. The channel consists of a Heisenberg chain with $xyz$ interaction model and the intrinsic decoherence is implemented through the Milburn model. It is shown that while the fidelity diminishes due to intrinsic decoherence, it may be enhanced if the channel is initially in an entangled state. It is also observed that, for stronger intrinsic decoherence, the initial entanglement of the channel is more effective in enhancing of fidelity.

Two two-level systems generated by su(2) algebra are initially prepared in a maximum nonsymmetric Bell state and having no mutual interaction. Each su(2)-system spatially interacts with two-mode cavity field in the nondegenerate parametric amplifier type cast through operators governed by su(1, 1) Lie algebra. An analytical description for the time evolution of the final state of the total system with the effect of intrinsic decoherence is found. Therefore, the robustness of the quantum correlations between the two su(2)-system is investigated by means of geometric quantum discord, measurement-induced nonlocality and negativity. We analyze in some detail the influence of initial coherence intensities, detuning and phase decoherence parameters on the steady-state correlation. We find that the steady-state correlations can be generated and enhanced by controlling the parameters of: the initial coherence intensities, the Bargmman index and the detuning. It is shown that the phenomenon of sudden death and re-birth of entanglement, and the sudden changes of the geometric quantum correlation can be controlled by these parameters. We find that the robustness of the quantum correlation can be greatly enhanced by the Bargmman index and the resonance detuning. Negativity is the measure most susceptible to phase decoherence, while geometric quantum discord and measurement-induced nonlocality are the more robust measures.