Atomic Wehrl Entropy Research Articles

Dynamics of phase space quasi-probability coherence of one of two moving atoms trapped in a cavity coherent field

This study explores the dynamics of atomic mixedness and phase space quasi-probability information of one of two moving atoms trapped in a cavity filled by a coherent field. The atom-photon interactions are considered with the resonance case through nonlinear intensity-dependent coupling. We investigate the impacts of the atom-photon and atomic motion couplings on the dynamics of the atomic Wehrl entropy's mixedness and phase space Husimi distribution information. By helping Wehrl entropy's mixedness dynamics, the dynamics of acceleration and enhancement of the generation of the atomic phase space quasi-probability coherence are examined, and the Husimi distributions of the generated atomic states of one of the two moving atoms are explored. The results are shown that the atomic Husimi distribution and Wehrl entropy's mixedness are susceptible to an increase in the atom-photon and the atomic motion couplings. Therefore, the atomic phase space Husimi distribution coherence can be improved by increasing the atomic motion and nonlinear atom-photon couplings.

Nonclassical atomic system dynamics time-dependently interacts with finite entangled pair coherent parametric converter cavity fields

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, the amplitudes and the 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.

On the degenerate and non-degenerate two-photon interaction between a two-level atom and a quantized two-modes: Entanglement and Pancharatnam phase

In this paper, we study the interaction between a two-level atom and a three types of nonlinear interaction of two modes, two as a degenerate two photon and the third of the converter form. The solution to the Schrodinger equation is obtained exactly under a certain specific condition. By using this solution we discuss numerically the atomic inversion, the degree of entanglement through the atomic Wehrl entropy, the geometric phase entropy for chosen values of the detuning and coupling parameters. Statistical properties of the investigated system is discussed by the evolution of the Mandel parameter.

Fisher information and quantum state estimation of two-coupled atoms in presence of two external magnetic fields

We consider a quantum system of an atom-atom interaction in the presence of two external magnetic and classical fields in x, and z directions. The dynamical behavior of single atom quantum quantifiers such as the atomic Wehrl entropy, atomic Fisher information and quantum entropy are investigated. The quantum entanglement degradation in regard to the atomic state estimation are discussed through the evolution of the atomic Fisher information flow, and the effects of the external classical fields and types of time dependent coupling between the two atoms are examined. We explore the relationship between different statistical quantities in the absence and presence of classical field during the time evolution. The results show that the creation and manipulation of entanglement by external fields greatly benefit within the suitable choice of the kind of time dependent coupling among the two atoms and external.

Aspects of Entropy Squeezing and Entanglement for Moving Two-Level Atom in Presence of Finite Trio Coherent State

In this paper, we investigate the entanglement of the interaction of three modes of radiation field with moving and unmoving two-level atom. The time evolution of the von Neumann entropy, entropy squeezing and marginal atomic Wehrl entropy is investigated. The marginal atomic Wehrl entropy as squeezing indicator of the entanglement of the system is suggested. The results beacon the important roles played by both the atomic motion parameters in the evolution of entanglement, entropy squeezing and marginal atomic Wehrl entropy. Using special values of the photon number of transition and atomic motion parameter, the entanglement phenomena of sudden death and long living entanglenment can be appeared. The results show that there is atomic motion monotonic harmonization atomic Wehrl entropy (WE). It is illustrated that the amount of the above-mentioned phenomena can be tuned by controlling the evolved parameters appropriately.

Some Statistical Properties for Interacting Between a Two Two-Level Atoms and the Electromagnetic Fields in Present of Converter Terms

Two two-level atoms interacting with a finite dimensional four-mode of radiation field is presented. The interaction of the field-field and the atom-field are considered. By using some canonical transformation, an exact solution of the wave function in the Schrodinger picture is obtained. The atomic inversion, the entropy squeezing, variance squeezing and scaled atomic Wehrl entropy phenomena are investigated. All theses phenomena are been controlled by finite state parameters and photon number operators.

Dynamic of Scaled Atomic Phase Entropy of a Single Two-Level Atom Interaction with SU(1,1) Quantum System

In this paper, we study the dynamics of the atomic inversion, scaled atomic Wehrl entropy and marginal atomic Q-function for a single two-level atom interacting with SU(1,1) quantum system. We obtain the wave function and system density matrix using specific initial conditions. We examine the effects of different parameter s on the scaled atomic Wehrl entropy, atomic Q-function and their marginal distribution. We observe an interesting monotonic relation between the different physical quantities for different values of the initial atomic position and detuning parameter

Entanglement Quantifier Based on Atomic Wehrl Entropy for Non-Linear Interaction between a Single Two-Level Atom and SU(1,1) Quantum System

In this paper, we study the dynamics of the atomic inversion, scaled atomic Wehrl entropy and marginal atomic Wehrl density for a single two-level atom interacting with SU(1,1) quantum system. We obtain the expectation values of the atomic variables using specific initial conditions. We examine the effects of different parameters on the scaled atomic Wehrl entropy and marginal atomic Wehrl density. We observe an interesting monotonic relation between the different physical quantities for different values of the initial atomic position and detuning parameter.

The influence of phase damping on a two-level atom in the presence of the classical laser field

In this paper we consider the influence of phase damping on the Jaynes–Cummings model (JCM) in the presence of the classical laser field. It is shown that for the temporal evolution of the atomic inversion a detuning parameter plays a role in delaying the effect of the damping. Our consideration is also extended to discuss the atomic Wehrl entropy and entropy squeezing. For the case of the marginal distribution, it is noted that the damping factor plays a considerable role in reducing the number of the fluctuations in the function behavior. On the other hand the damping factor removes the phenomenon of squeezing from both quadratures of the entropy squeezing.

Quantum and Classical Quantifiers for Atom-Nonlinear Field System under Decoherence

The entanglement and coherence of a single qubit and deformed bosonic field inside a phase-damped cavity are discussed. In the classical q → 1 limit, analytic results under certain parametric conditions are obtained. The influence of deformation and dissipation on the negativity, Wehrl entropy, atomic Wehrl entropy and marginal distribution is studied. An interesting relation between the entanglement, deformation and decoherence effects is observed.

Dynamical Properties of Scaled Atomic Wehrl Entropy of Multiphoton JCM in the Presence of Atomic Damping

We study the dynamics of the atomic inversion, scaled atomic Wehrl entropy, and marginal atomicQ-function for a single two-level atom interacting with a one-mode cavity field taking in the presence of atomic damping. We obtain the exact solution of the master equation in the interaction picture using specific initial conditions. We examine the effects of atomic damping parameter and number of multiphoton transition on the scaled atomic Wehrl entropy, atomicQ-function, and their marginal distribution. We observe an interesting monotonic relation between the different physical quantities in the case of different values of the number of photon transition during the time evolution.

Full-trapped three-level ion in the lamb–dicke limit: analyzing and comparing quantum entanglement measures of two qudits

Our aim is to investigate the entanglement dynamics and quantum correlations of a full-trapped ion interacting with two time-independent laser beams in view of the Lamb–Dicke parameter. For this purpose, the three probability amplitudes in the trapped ion is taken as $ \sqrt {{{{1} \left/ {3} \right.}}} $ . Concurrence, negativity, and atomic Wehrl entropy of entanglement exhibit a long interacting time. We show that long survival is proved with these quantum measures.

Analysis of mixed state entanglement with intrinsic decoherence

We analyze different entanglement measures for a mixed state two-level system in the presence of intrinsic decoherence. The information about entanglement is obtained by comparing the results for the atomic Wehrl entropy and negativity with the analytical results for a simple case. For the strong decoherence case we find that a similar and long-lived maximum Wehrl entropy and negativity between atom and field are shown. The results highlight the important roles played by both the decoherence parameter and the initial state setting in determining the evolution of the atomic Wehrl entropy and negativity.

Atomic Wehrl entropy and negativity as entanglement measures for qudit pure states in a trapped ion

We analyze the atomic Wehrl entropy and negativity as compared with concurrence for qudit pure states in a trapped ion. We use the density matrix in calculating the three measures of quantum correlations. We find that a long surviving entangled qudit can be established between the three atomic levels and vibrational modes. We observe three distinct entanglements in response to an increasing Lamb–Dicke parameter.

ATOMIC WEHRL ENTROPY OF A SINGLE QUBIT SYSTEM

We propose the use of atomic Wehrl entropy associated to the reduced atomic density operator as an entanglement indicator of bipartite systems. This is applied to a two-level system (one single harmonically trapped ion) by taking into account the linear center-of-mass-motional degree of freedom. Detailed analytical and explicit expressions are given, taking into account different configurations. The results show the important roles played by the laser phase and initial state setting in the evolution of the atomic Q-function, atomic Wehrl entropy and marginal atomic Q-function. Our procedure of using atomic Wehrl entropy may be applied to a system with Hilbert space of high dimension.

WEHRL ENTROPY OF A MIXED STATE THREE-LEVEL ATOM INTERACTING WITH A CAVITY FIELD

In this paper, the Wehrl entropy approach is discussed and compared with the quantum entanglement using a mixed-state three-level atom interacting with a cavity field. In the pure state case, the behavior of the atomic Wehrl entropy shows the same behavior of the entanglement due to the von-Neumann entropy, while the mixed state case gives the total correlation due to quantum mutual entropy. If the system is in an entangled state, the formalism can be used to quantify the entanglement as well as the total correlations.

Entanglement evaluation with atomic Fisher information

In this paper, the concept of atomic Fisher information (AFI) is introduced. The marginal distributions of the AFI are defined. This quantity is used as a parameter of entanglement and compared with linear and atomic Wehrl entropies of the two-level atom. The evolution of the atomic Fisher information and atomic Wehrl entropy for only the pure state (or dissipation-free) of the Jaynes–Cummings model is analyzed. We demonstrate the connections between these measures.

The atomic Wehrl entropy of a V-type three-level atom interacting with two-mode squeezed vacuum state

We study the interaction of a V-type three-level atom with a two-mode field through the two-photon interaction when the atom is initially in the upper state and the initial field is in the two-mode squeezed vacuum state. The influence of the atomic motion on the evolution of the atomic Q-function and atomic Wehrl entropy is examined. The results show that the atomic motion and the mode structure play important roles in the evolution of the atomic Q-function, atomic Wehrl entropy, and marginal atomic Wehrl entropy.

Atomic Wehrl entropy for the Jaynes–Cummings model: explicit form and Bloch sphere radius

For the interaction between a two-level atom and the radiation field in the dipole and the rotating wave approximations, namely, the Jaynes–Cummings model, we obtain a closed form for the atomic Wehrl entropy in terms of the Bloch sphere radius. This explains analytically why the atomic Wehrl entropy has an identical behavior to that of the von Neumann entropy.

WEHRL ENTROPY AND ENTANGLEMENT OF A TIME-DEPENDENT TWO-LEVEL TRAPPED ION INTERACTING WITH A LASER FIELD

The time evolution of the atomic Wehrl entropy and long-lived entanglement generation using a single trapped ion interacting with a laser field are analyzed. Starting from the Heisenberg equation of motion, an exact solution of the system is obtained by indicating that there are some interesting features when a time-dependent modulating function is considered. We demonstrate that the long-living quantum entanglement can be obtained using the time-independent interaction when the field is initially in a pair cat states.