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In this paper, we present a new encryption method based on discrete wavelet transform (DWT). This method provides a number of advantages as a pseudo randomness and sensitivity due to the variation of the initial values. We start by decomposing the image with spatial reconstruction by DWT, followed by preformation by fractional chaotic cryptovirology and Henon map keys for space encryption. Bearing in mind the rapid pace of change in the fields of fractional chaotic cryptovirology, our findings suggest that the proposed method is too powerful relative to the key sensitivity, histogram, entropy and correlation coefficient. [ABSTRACT FROM AUTHOR]

Background: Over-prescription of antibiotics contributes to antibiotic resistance, which is a global health threat. Egypt has alarmingly high rates of antibiotic over-prescription for acute upper respiratory tract infections (URIs) in children. To effectively address this issue, it is important to understand the various factors that influence prescription behaviors. The Teixeira antibiotic prescription behavioral model (TAPBM) offers a comprehensive framework through which these factors can be explored. This qualitative study sought to investigate the perspectives of key stakeholders involved in pediatric healthcare in Egypt, with the primary goal of identifying the underlying determinants that contributed to this problem. Methods: This qualitative study was conducted in Assiut City, Egypt, between January and March 2023. Purposive sampling was used to select participants, including consultant pediatricians, supervisors of pediatric training programs, and specialists in infection prevention and control. Thirteen semi-structured in-depth interviews (IDIs) were conducted, audio-recorded, and transcribed. Thematic analysis was performed using MAXQDA 2020 software. Results: Two main themes emerged from the analysis: intrinsic factors related to physicians, extrinsic factors related to patients, and nonphysician factors. Intrinsic factors encompass personal characteristics and attitudes. Prescribing decisions were influenced by factors such as fear of complications, limited follow-up visits, and competition. Knowledge and education also played a significant role. Moreover, diagnostic uncertainty in distinguishing between bacterial and viral infections posed a challenge. Extrinsic factors included patient and caregiver factors, such as parental expectations and demands for antibiotics, driven by the belief that they produced rapid results. Moreover, patients' demographic factors, including socioeconomic status and living conditions, affected their prescribing behavior. Health system-related factors, such as the type of healthcare institution and the absence of formal national guidelines, were identified as influential factors. Additionally, this study highlighted the influence of the pharmaceutical industry. The potential impact of the COVID-19 pandemic on antibiotic prescriptions was addressed. Conclusions: The study highlights the intricate interplay between intrinsic and extrinsic factors that shape antibiotic prescription decisions, underscoring the significance of addressing these factors in mitigating overprescribing. [ABSTRACT FROM AUTHOR]

We investigate some new aspects of the nonlinear interaction between a three-level Ξ -type atom and bimodal field. The photon-assisted atomic phase damping, detuning parameter, Kerr nonlinearity and the time-dependent coupling have been considered. The general solution has been obtained by using the Schrődinger equation when the atom and the field are initially prepared in the excited state and coherent state, respectively. The atomic population inversion and concurrence are discussed. It is shown that the time-dependent coupling parameter and the detuning parameter can be considered as quantum controller parameters of the atomic population inversion and quantum entanglement in the considered model. [ABSTRACT FROM AUTHOR]

In this article we suggest the entire functions associated with the L-functions attached to cusp forms. The entire function defined by the Fourier cosine transform is the solution for the diffusion equation in 1-D case. We propose three conjectures for the zeros of three entire functions of order one via theory of entire functions. [ABSTRACT FROM AUTHOR]

In this article we suggest a new odd entire function of order one. We discover that it is the solution of the heat equation. We propose a new conjecture that this function has only real zeros. The obtained result gives a connection with the heat problem and number theory. [ABSTRACT FROM AUTHOR]

In this article, we address a new model for the scaling law heat conduction problem by using the scaling law vector calculus associated with the Korcak scaling law. The scaling law heat conduction equations are discussed in detail. The scaling law vector calculus formulas are proposed as an efficiently mathematical tool to describe the Korcak scaling -law phenomena in heat transport system. [ABSTRACT FROM AUTHOR]

This paper is devoted to analyzing a new model of a coupled Langevin system with fractional operators under nonlocal antiperiodic integral boundary conditions. This model involves nonlinear Langevin fractional equations with Caputo–Hadamard and Caputo fractional operators. Also, the existence and uniqueness of solutions to the suggested model have been investigated by the fixed-point technique. Moreover, the Hyers–Ulam stability of the solutions has been discussed. Finally, we provide an illustrative example to support the theoretical results. [ABSTRACT FROM AUTHOR]

The use of the so-called entropic inequalities is revisited in the light of new quantum correlation measures, specially nonlocality. We introduce the concept of classicality as the nonviolation of these classical inequalities by quantum states of several multiqubit systems and compare it with the nonviolation of Bell inequalities, that is, locality. We explore-numerically and analytically-the relationship between several other quantum measures and discover the deep connection existing between them. The results are surprising due to the fact that these measures are very different in their nature and application. The cases for $$n=2,3,4$$ qubits and a generalization to systems with arbitrary number of qubits are studied here when discriminated according to their degree of mixture. [ABSTRACT FROM AUTHOR]

Given a perfect superposition of states on a quantum system of qubits. We propose a fast quantum algorithm for collapsing the perfect superposition to a chosen quantum state without applying any measurements. The basic idea is to use a phase destruction mechanism. Two operators are used, the first operator applies a phase shift and a temporary entanglement to mark in the superposition, and the second operator applies selective phase shifts on the states in the superposition according to their Hamming distance with . The generated state can be used as an excellent input state for testing quantum memories and linear optics quantum computers. We make no assumptions about the used operators and applied quantum gates, but our result implies that for this purpose the number of qubits in the quantum register offers no advantage, in principle, over the obvious measurement-based feedback protocol. [ABSTRACT FROM AUTHOR]

We propose a new formulation of quantum algorithm which allows to distribute amplitudes over two copies of small quantum subsystems. The new method gives a fixed number of copies and applied to the control of multi-qubit system. The analysis for the amount of error due to the distribution process has been presented for a system of 10 qubits with a small quantum subsystems to be copied. The present scheme provides a new way to distribute amplitudes over small quantum subsystems. [ABSTRACT FROM AUTHOR]

Abstract: We report on the observation of new features in a superconducting charge qubit system. The system we analyze comprises of a single Cooper-pair box sequentially coupled to two microwave cavity fields. Simulations of the full qubit–field dynamics show significant total correlation and coherence loss. By suitably choosing the system’s parameters and precisely controlling the dynamics, we demonstrate the generation of two-mode field states. We explore the nonclassical behavior of the system by studding the quasi-probability distribution function. Our scheme can be realized within the current experimental technology and may well be of use in quantum information processing applications. [Copyright &y& Elsevier]

Abstract: We propose a method for analyzing Berry phase for a multi-qubit system of superconducting charge qubits interacting with a microwave field. By suitably choosing the system parameters and precisely controlling the dynamics, novel connection found between the Berry phase and entanglement creations. [Copyright &y& Elsevier]

Abstract: We have considered a system of two superconducting charge qubits capacitively coupled to a microwave resonator. By means of the Bloch vectors and cross dyadic we quantify the degree of entanglement contained in the generated entangled state in different regimes. We show the important roles played by initial state settings, coupling constant and the mean photon number on generating entangled states with high degree of entanglement and high capacity. [Copyright &y& Elsevier]

Abstract: Motivated by recent experiments [Y.A. Pashkin, T. Yamamoto, O. Astafiev, Y. Nakamura, D.V. Averin, J.S. Tsai, Nature 421 (2003) 823] that show coherent oscillations of two superconducting qubits system, we consider a system of two charge qubits coupled to a common stripline microwave resonator. We discuss the separable and entangled behavior as well as the quantum and classical information deficits. Numerical computation of these quantities is performed for several regimes. We find that for less entangled states the partner can extract much more information by means of classical communication and local operations. [Copyright &y& Elsevier]

Abstract: In this communication we introduce a new model which represents the interaction between an atom and two fields injected simultaneously within a cavity including the nonlinear couplers. By using the canonical transformation the model can be regarded as a generalization of several well-known models. We calculate and discuss entanglement between the tripartite system of one atom and the two cavity modes. For a short interaction time, similarities between the behavior based on our solution compared with the other simulation based on a numerical linear algebra solution of the original Hamiltonian with truncated Fock bases for each mode, is shown. For a specific value of the Kerr-like medium defined in this letter, we find that the entanglement, as measured by concurrence, may terminate abruptly in a finite time. [Copyright &y& Elsevier]

We analyze a controllable generation of maximally entangled mixed states of a circuit containing two-coupled superconducting charge qubits. Each qubit is based on a Cooper pair box connected to a reservoir electrode through a Josephson junction. Illustrative variational calculations were performed to demonstrate the effect on the two-qubits entanglement. At sufficiently deviation between the Josephson energies of the qubits and/or strong coupling regime, maximally entangled mixed states at certain instances of time is synthesized. We show that entanglement has an interesting subsequent time evolution, including the sudden death effect. This enables us to completely characterize the phenomenon of entanglement sharing in the coupling of two superconducting charge qubits, a system of both theoretical and experimental interest. [ABSTRACT FROM AUTHOR]

Abstract: Adopting the framework of two-coupled superconducting charges model, we derive a general formula for the total correlation function between the two charge qubits initially prepared in a mixed state. The impact of the different parameters of the system is explicitly investigated. We have identified a class of two-qubit states that have rich dynamics when the deviation between the characteristic energies of the charge qubits tends to a minimum value. Present calculations show that the total correlation decreases abruptly to zero in a finite time due to the influence of the decoherence. [Copyright &y& Elsevier]

Abstract: We construct a complete representation of the atomic information entropy of an arbitrary multi-level system. Our approach is applicable to all scenarios in which the quantum state shared by a single particle and fields is known. As illustrations we apply our findings to a single four-level atom strongly coupled to a cavity field and driven by a coherent laser field. In this framework, we discuss connections with entanglement frustration and entropic forms. We conclude by showing how the atomic information entropy can be extended to examine entanglement in multi-level atomic systems. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

This contribution describes some new features of quantum entanglement in a single three-level trapped ion confined in a two-dimensional (2D) harmonic potential. The dynamical properties of quantum entanglement are studied in terms of the reduced-density linear entropy considering two specific initial states of the field. Allowing the instantaneous position of the centre-of-mass motion of the ion to be explicitly time dependent, it is shown that either sudden death of entanglement or survivability of quantum entanglement can be obtained with a specific choice of the initial state parameters. The difference in evolution picture corresponding to the multi-quanta processes is discussed. [ABSTRACT FROM AUTHOR]

Abstract: The dynamical properties of quantum entanglement in two effective two-level trapped ions interacting with a laser field are studied in terms of the negative eigenvalues of the partial transposition of the density operator. In contrast to the usual belief that destroying the entanglement can be observed due to the environment, it is found that the Stark shift can also produce sudden death of entanglement and long-lived entanglement between the qubits that are prepared initially in separable states or mixed states. [Copyright &y& Elsevier]

Abstract: Based on exact quantum dynamics of a single four-level atom strongly coupled to a cavity field mode and driven by a coherent laser field, we investigate quantum mutual entropy as a measure of the amount of total correlations. Through the analysis of the dynamic of the total correlation, we show that under the influence of the decoherence, the total correlation may terminate abruptly in a finite time. Further consequences of our results include a description of total correlations of a general multi-level atomic system. [Copyright &y& Elsevier]

Abstract: We explore and develop the mathematics of the theory of a class encompassing several widely encountered models of a solid-state quantum structure which is capable of generating maximally entangled states, such as Bell-states and Greenberger–Horne–Zeilinger (GHZ) states. This analytical treatment not only provides an unified formulation to the models belonging to the class considered but is found to uncover several new results for physical systems possessing multi-particles interaction. The concept of entanglement fidelity is used to construct explicitly general features of the system which is postulated to satisfy the maximum entangled states generation conditions. The laser pulses necessary to generate these maximally entangled states are given explicitly. We show that the fidelity yields a structure that is analogous in many respects to that of maximum entanglement. These results have significant implications for quantum dots-based information processing. The results are illustrated with an application to a specific wide-gap semiconductor quantum dots system, like Zinc Selenide (ZnSe)-based quantum dots. The scheme for generating GHZ state using quantum dots model could be implemented using technology that is currently being developed. [Copyright &y& Elsevier]

The geometric phase of a three-level atom interacting with single-mode in the presence of the one-dimensional photonic band gap material is studied. We consider dipole emitters situated in the thin slab region between two semi-infinite one-dimensionally periodic photonic crystals, a situation reminiscent of planar cavity laser structures. It shows that the Pancharatnam phase depends crucially on the presence of the photonic band gap. This feature is attributed to the fact that in the photonic band gap region electromagnetic modes are not allowed to propagate into the dielectric slab and hence no interaction can take place in this region. The outcomes are illustrated with numerical simulations applied to GaAs. [ABSTRACT FROM AUTHOR]

Abstract: We present an analytical expression for the response of a transient spectrum to a single-Cooper-pair box biased by a classical voltage and irradiated by a single-mode quantized field. The exact solution of the model is obtained, by means of which we analyze the analytic form of the fluorescence spectrum using the transitions among the dressed states of the system. An interesting relation between the fluorescence spectrum and the dynamical evolution is found when the initial field states are prepared in binomial states. [Copyright &y& Elsevier]

Abstract: The exciting new features of entanglement are burgeoning with revolutionary new advances in the areas of quantum communication, quantum information processing and quantum computing. We review recent theoretical studies and applications of pure and mixed states entanglement of trapped ions interacting with a laser field. After an introduction to the basic concepts of traditional entanglement measures and methodology, the main phenomena and observations of two-, three- and four-level systems are summarized. In particular, we explore the influence of the various parameters of these systems on the entanglement. The particular advantages of using atomic Wehrl entropy and Shannon entropy are highlighted. A general expression of the mixed state entanglement is obtained with the physical significance and without the diagonal approximation. Based on this result, we provide a general expression for the entanglement in a multi-level system. We show that the mixed-state and specific eigenstates of the two or three-level system posses remarkable entanglement properties that can reveal new insight into quantum correlations present in the multi-level models. Furthermore, we propose an intuitive picture of the behavior of mixed-state entanglement in the presence of the decoherence. After a short presentation of the entanglement measures of two qubits, each defined as an effective two-level system (negativity, Bures metric and concurrence) we discuss the general behaviors of the concurrence as a measure of entanglement. We identify and numerically demonstrate the region of parameters where significantly large entanglement can be obtained. Most interestingly, it is shown that features of the entanglement are influenced significantly when the multi-photon process is involved. [Copyright &y& Elsevier]

Entropy squeezing is examined in the framework of Shannon information entropy for a degenerate Raman process involving two degenerate Rydberg energy levels of an atom interacting with a single-mode cavity field. Quantum squeezing in entropy is exhibited via the entropic uncertainty relation. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we extend earlier investigations (Q.C. Zhou, S.N. Zhu, Opt. Commun. 248 (2005) 437) on the pure state entanglement to the mixed state entanglement. In particular, analysis of the pattern of entanglement arising in the interaction between a three-level trapped ion with a time-dependent frequency interacting with a laser field is presented. By working out an exact analytic solution, we conclusively calculate the mixed state entanglement formula. Numerical calculations under current experimental conditions are carried out. Depending on the initial state of the system and in the presence of a time-dependent interaction, long surviving entanglement between the trapped ion and field can be obtained. [Copyright &y& Elsevier]

Abstract: A new version of two multi-level trapped atoms interacting with laser fields is under consideration. This system is based on a three-level trapped atom interacting with laser fields in the presence of another three-level trapped atom taking into account the time-dependent atom-field couplings and phase shift. The entanglement due to the concurrence is calculated and its time evolution phenomena is demonstrated within the framework of the presented theory. Our results establish an explicit relationship between the concurrence and the entanglement through the two three-level atoms and the fields interaction. We show that different nonclassical effects arise in the dynamics of the atomic population inversion, due to the initial states of the system as well as the values of the Lamb–Dicke parameter. [Copyright &y& Elsevier]

With the reliance in the processing of quantum information on a cold trapped ion, we analyze the entanglement entropy in the ion-field interaction with pair cat states. We investigate a long-living entanglement allowing the instantaneous position of the center-of-mass motion of the ion to be explicitly time-dependent. An analytic solution for the system operators is obtained. We show that different nonclassical effects arise in the dynamics of the population inversion, depending on the initial states of the vibrational motion. We study in detail the entanglement degree and demonstrate how the input pair cat state is required for initiating the long-living entanglement. This long-living entanglement is damp out with an increase in the number difference q. Owing to the properties of entanglement measures, the results are checked using another entanglement measure (high order linear entropy). [ABSTRACT FROM AUTHOR]

Abstract: The problem of a single two-level atom in its excited state, placed in a bimodal cavity in which an arbitrary form of the intensity-dependent atom–field coupling is present, is solved exactly. Expressions for the energy eigenvalues and eigenvectors are derived, and an exact representation for the time-dependent unitary evolution operator of the system is given, by means of which we analyze the analytic form of the fluorescence spectrum using the transitions among the dressed states of the system. The influence of parameter misfits on the quantum system is discussed. An interesting relation between the fluorescence spectrum and the dynamical evolution is found when the initial field states are prepared in properly intelligent states. By comparison with exact numerical results, we demonstrate that features of the fluorescence spectrum are influenced significantly by the different kinds of the nonlinearity of the intensity-dependent atom–field coupling. We provide numerous examples to illustrate this correspondence, and provide evidence of its usefulness. The present work considerably extends earlier results for two-level systems. [Copyright &y& Elsevier]

This communication is an enquiry into the circumstances under which concurrence and phase entropy methods can give an answer to the question of quantum entanglement in the composite state when the photonic band gap is exhibited by the presence of photonic crystals in a three-level system. An analytic approach is proposed for any three-level system in the presence of photonic band gap. Using this analytic solution, we conclusively calculate the concurrence and phase entropy, focusing particularly on the entanglement phenomena. Specifically, we use concurrence as a measure of entanglement for dipole emitters situated in the thin slab region between two semi-infinite one-dimensionally periodic photonic crystals, a situation reminiscent of planar cavity laser structures. One feature of the regime considered here is that closed-form evaluation of the time evolution may be carried out in the presence of the detuning and the photonic band gap, which provides insight into the difference in the nature of the concurrence function for atom-field coupling, mode frequency and different cavity parameters. We demonstrate how fluctuations in the phase and number entropies affected by the presence of the photonic-band-gap. The outcomes are illustrated with numerical simulations applied to GaAs. Finally, we relate the obtained results to instances of any three-level system for which the entanglement cost can be calculated. Potential experimental observations in solid-state systems are discussed and found to be promising. [ABSTRACT FROM AUTHOR]

An exact solution of the time-dependent master equation that describes the evolution of two two-level qubits (ions or atoms) within a perfect cavity for the case of multiphoton transition and in the presence of both the Stark shift and phase shift is obtained. Employing this solution, the significant features of the entanglement when a second qubit is allowed to interact with cavity mode and becomes entangled with the first qubit are investigated in the context of the measure defined by negative eigenvalues for the partial transposition of the density operator. The effects of Stark shift, distance between the two qubits, and an instantaneous phase shift experienced by the second qubit on the entanglement and probability amplitudes are indicated. It has been shown that the entanglement as well as the intensity are markedly affected by different parameters when the nonlinear two-photon process is involved. Moreover, the quasiprobability distribution function is investigated before and after the sudden phase shift experienced by the second qubit. We believe that this may throw some light on the question of the entanglement of multi-qubit systems. [ABSTRACT FROM AUTHOR]

In the present communication we consider a time dependent ion-field interaction. Here we discuss the interaction between a single trapped ion and two fields taking into account the coupling parameter to be time dependent and allowing for amplitude modulation of the laser field radiating the trapped ion. At exact resonances the analytic solution for the Heisenberg equations of motion is obtained. We examine the effect of the velocity and the acceleration on the Rabi oscillations by studying the second order correlation function. The phenomenon of squeezing for single and two fields cases is considered. The cross correlation between the fields is discussed. [ABSTRACT FROM AUTHOR]

In this paper, an entanglement measure due to quasi-mutual entropy from initially entangled mixed states of a three-level atom interacting with a single cavity field is introduced. Detailed analytical and explicit expressions are given taking into account an arbitrary form of the intensity-dependent coupling. Despite its simplicity the model exhibits a very broad range of intricate physical effects and it is widely used in quantized theories of laser. We show that quantum revivals are possible for a broad continuous range of physical parameters in the case of initial coherent states. Entanglement degree effects are shown to be very sensitive to the initial state of the system. Numerical calculations under current experimental conditions are taken into account and it is found that the intensity-dependent coupling changes the general features dramatically. [ABSTRACT FROM AUTHOR]

Few epidemiological surveys have been carried out to determine the prevalence of skin diseases in the population of Egypt, particularly “Upper Egypt”. So it is a pressing necessity to conduct such a study in rural Assiut. To determine the prevalence of various skin diseases in rural Assiut. A cross-sectional community-based survey was followed. The survey included 8008 rural inhabitants of all ages and both sexes from a representative of three villages of Assiut Governorate, Upper Egypt. The data were collected through personal interview and examination at homes from December 1994 to December 1996. They showed that 6961 (86.93%) of the studied population had one or more skin diseases. The group with parasitic skin infestations had the highest prevalence rate (27.40%) of the total sample, of which pediculosis capitis (19.37%) was the commonest. Eczema/dermatitis group had a rate of 19.82%, with pityriasis alba forming the majority (13.49%). Pigmentary disorders were 17.68%, followed by fungal skin infections (16.17%), then naevoid disorders (16.10%), hair and scalp disorders (12.07%), bacterial skin infections (10.10%), sweat gland disorders (6.16%), acne vulgaris (5.37%). Leprosy constituted 1.6/10,000. Other various skin disorders were recorded. Infective-parasitic diseases were a major problem particularly among the younger age-group and those of low socio-economic status. [ABSTRACT FROM AUTHOR]

A general formalism of a three-level atom single-mode system by including arbitrary forms of nonlinearities of both the field and the intensity-dependent atom–field coupling is proposed. With an arbitrary initial condition, an exact analytical time-dependent solution is presented. The work here extends previous studies in this context. Under the condition of an initial coherent field, the atomic-level occupation probability shows the collapse–revival phenomena, which have different features with different forms of the nonlinearities. We derive an expression for the Pancharatnam phase for the entangled state of the system. It is shown that the Pancharatnam phase explicitly contains information about the statistics of the field and atomic coherence. Also, the influences of the nonlinearities on the squeezing phenomenon and the correlation functions are examined. [Copyright &y& Elsevier]

In this communication we examine the field entropy and the degree of entanglement for a time dependent Jaynes–Cummings model. We have allowed the amplitude of the laser field irradiating a trapped ion to be modulated. A sinusoidal modulation depending on a quadratic function in the argument is considered. At exact resonances the analytic solution for the wave function is given, and the density matrix operator is obtained. We show that for a small value of the acceleration the entanglement between the field and the atom would delay, while for a large value of the acceleration the entanglement decreases its value. We have also shown that the effect of the velocity is different from that of the acceleration where the value of the entropy decreases as we increase the value of its parameter. [Copyright &y& Elsevier]

We generalize a study of the behavior of a three-level atom in a single-mode mazer. Our formulation takes into account the interaction region and the spatial variation along the cavity axis. A general analytic time-dependent solution is obtained, and some special cases reduce to very simple expressions. When propagation effects are taken into consideration, the emission probability is in uenced significantly. We provide the necessary arguments to justify the validity of our conclusions for emission probability and micro-maser whose dynamics is governed by the wave function. Our main conclusion is that in the present system, the inclusion of the spatial dependence of the cavity region is necessary and important. We provide numerous examples to illustrate this correspondence, and provide evidence of its usefulness. [ABSTRACT FROM AUTHOR]

In this paper, we consider a unified approach to study the degree of entanglement of two-level systems interacting with a quantized electromagnetic field. We investigate a range of parameters in a generalized Jaynes-Cummings model (JC-model) with intensity-dependent, field nonlinearity and nonresonant coupling. In terms of the density matrix and without the diagonal approximation we derive an explicit expression for the entanglement degree using a function analogous to mutual entropy. This notion is inspired by the fact that the quantum state may be interpreted as a measure of information. With the aid of the quasiprobability distribution function, the statistical properties of the field are analyzed. It is shown that when the atom is initially in its upper-level and the one-photon at resonance, the Q-function splits into two peaks and counter rotate in phase space. [ABSTRACT FROM AUTHOR]

In this article a treatment of a three-level atom interacting with two modes of light in a cavity with arbitrary forms of nonlinearities of both the fields and the intensity-dependent atom-field coupling is presented. A factorization of the initial density operator is assumed, with the privileged field modes being in a pair-coherent state. We derive and illustrate an exact expression for the time evolution of the density operator, by means of which we identify and numerically demonstrate the region of parameters where significantly large entanglement can be obtained. We show that entanglement can be significantly influenced by different kinds of nonlinearities. The nonlinear medium yields the superstructure of atomic Rabi oscillation. We propose a generation of Bell-type states having a simple initial state preparation of the present system [ABSTRACT FROM AUTHOR]

In this essay we introduce a new Hamiltonian which represents the interaction between a three-level atom and a single electromagnetic field including arbitrary forms of nonlinearities of both the field and the intensity-dependent coupling. We derive an exact solution for the density operator of the system by means of which we study the field purity for the entangled state of the system. Also, the influences of the nonlinearities on the field purity and mean photon number are examined. Under the condition of an initial coherent field, the field purity shows the collapse-revival phenomenon. It is found that features of these phenomenon are sensitive to the changes of different kinds of the nonlinearities. [ABSTRACT FROM AUTHOR]

We present a detailed theory of a general formalism of a nonlinear JC-model. In particular we explicitly take into account forms of nonlinearities of both the field and the intensity-dependent atom-field coupling and study the properties of the fluorescence spectrum in this system. The exact solution for time-dependence of the atom-field system is obtained, by means of which we analyze the analytic form of the fluorescence spectrum produced by an atom in an ideal cavity using the transitions among the dressed states of the system. We investigate the influences of the nonlinearities on the fluorescence spectrum, for initial squeezed, thermal and coherent states. It is shown that features of the fluorescence spectrum are significantly influenced by the kinds of nonlinearities of the single-mode field. [ABSTRACT FROM AUTHOR]

In this paper, we use the quantum field entropy to measure the degree of entanglement in the time development of a three-level atom interacting with two-mode fields including all acceptable kinds of nonlinearities of the two-mode fields. This model describes a very general situation in which the system admits two detuning parameters and includes an arbitrary form of the nonlinearity of the two modes. It is shown that when the individual modes of the field are detuned far from the intermediate atomic level, the dynamic Stark shift is induced by the nonlinear medium. The results show that the nonlinearity effect yields the superstructure of atomic Rabi oscillations and changes the quasiperiod of the field entropy evolution and entanglement between the atom and the field. The general conclusions reached are illustrated by numerical results. [ABSTRACT FROM AUTHOR]

We propose a general formalism of a nonlinear Jaynes–Cummings-model by including possible forms of nonlinearities of both the field and the intensity-dependent atom-field coupling. We obtain an exactly analytic solution of the model, by means of which we identify and numerically demonstrate the region of parameters where significantly large entanglement can be obtained. Under the condition of an initial coherent field, the atomic inversion shows the collapse-revival phenomenon, which have different features in different forms of the nonlinearities. It is shown that features of the degree of entanglement is influenced significantly by the kinds of the nonlinearities of the single-mode field. The influences of the nonlinearities on the photon number distribution and phase properties are examined. [Copyright &y& Elsevier]

In this communication we introduce a new model of Hamiltonian which represents the interaction between a two-level atom and two electromagnetic fields injected simultaneously within a cavity. By using the canonical transformation the model can be regarded as a generalization of the Jaynes–Cummings model (JCM). The relationship between the original and new states has been established, and the exact expression for the wave function in Schro¨dinger picture is obtained. The atomic inversion and the degree of entanglement are considered. We find that the revival time is different from what has been observed in the JCM case. [Copyright &y& Elsevier]

The emission probability of a cold atom in a microcavity when its center-of-mass motion is described quantum mechanically is presented, but is distinguished from other treatments by the inclusion of the spatial variation along the cavity axis. In particular, the mesa mode cavity profile is considered. The quantum theory of the one-photon mazer is constructed in the framework of the dressed-state coordinate formalism. Simple expressions for the atomic populations, the cavity photon statistics, and the reflection and transmission probabilities are given for any initial state of the atom-field system. The general conclusions reached are illustrated by numerical results. [ABSTRACT FROM AUTHOR]

We introduce a new framework for quantum two-spin correlations based on a quantum skew information quantity and long-negativity. The quantum correlations for an anisotropic two-qubit Heisenberg X Y Z model are affected by physical parameters such as intrinsic decoherence, Werner states and time-dependent magnetic fields. In particular, the joint effects of Werner states, magnetic fields and anisotropic parameters on quantum correlation robustness are investigated in the presence of intrinsic decoherence. For an initially uncorrelated state, robust entanglement is generated while skew information between the two quantum bits no longer exists. It is shown that the magnetic field makes the system strongly correlated with incredibly significant steady-state values in uncorrelated states. The phenomenon of sudden death and sudden birth appear during the evolution process of initial conditions. Finally, if the system starts from a mixed state or a Werner state, the magnetic field does not play a significant role in the monotonically decreasing correlations. By leveraging our framework, one can create a kind of stability between the uncertainty-induced quantum nonlocality and the local quantum uncertainty correlations. [ABSTRACT FROM AUTHOR]

This article mainly concentrates on the synchronization problem for a more general kind of the master–slave memristor-based neural networks with fractional derivative. By applying a continuous-frequency-distributed equivalent model tool, some new outcomes and sufficient conditions on the robust synchronization of the master–slave neural networks with uncertainty are proposed via linear matrix inequality (LMI). Finally, two memristive neural networks model with fractional derivatives are presented to validate the efficiency of the theoretical results. [ABSTRACT FROM AUTHOR]

This article investigates the issue of anti‐modal‐asynchrony sliding mode control (SMC) for discrete semi‐Markov jump systems with bi‐boundary sojourn time. Asynchronous mechanism refers to the mismatch phenomenon between the system mode and the controller mode, in which the modal lag is mode‐dependent to reduce some conservatism compared with traditional mode‐independent lag. In contrast to traditional semi‐Markov jump systems, the sojourn time of each mode in this article is considered to have upper‐and‐lower bounds, representing better characteristics than the upper bound. Based on the semi‐Markov kernel and the Lyapunov function related to the elapsed time of current mode, a sufficient condition is proposed to ensure that the mean‐square stability of the underlying system is achieved under an equivalent SMC mechanism. The conditions for the existence of the designed controller are obtained, which shows that the constructed SMC mechanism is effective against asynchronous mode jumps. An anti‐modal‐asynchrony SMC mechanism is constructed to achieve the reachability of discrete quasi‐sliding mode. Finally, the F‐404 aircraft engine model is given to validate the effectiveness of the control strategy. [ABSTRACT FROM AUTHOR]