Mandel Parameter Research Articles

Photon-Added Deformed Peremolov Coherent States and Quantum Entanglement

In the present article, we build the excitedcoherent states associated with deformed su(1,1) algebra (DSUA), called photon-added deformed Perelomov coherent states (PA-DPCSs). The constructed coherent states are obtained by using an alterationof the Holstein–Primakoff realization (HPR) for DSUA. A general method to resolve of the problem of the unitary operator was developed for these kinds of quantum states. The Mandel parameter is considered to examine the statistical properties of PA-DPCSs. Furthermore, we offer a physical method to generate the PA-DPCSs in the framework of interaction among fields and atoms. Finally, we introduce the concept of entangled states for PA-DPCSs and examine the entanglement properties for entangled PA-DPCSs.

Statistical properties of the 𝒜κ<0 Weyl–Heisenberg algebra coherent states

In this paper, we study the one-parameter [Formula: see text]-generalized oscillator algebra [Formula: see text] (which includes the case of the standard Weyl–Heisenberg algebra). This algebra admits representations of finite-dimensional for negative values of the parameter [Formula: see text]. We construct the associated Perelomov like coherent states. We discuss their statistical properties. In particular, we derive the expressions of the Mandel parameter and Husimi function and we discuss the squeezing of the [Formula: see text] coherent states.

Properties of new even and odd nonlinear coherent states with different parameters

We construct a class of nonlinear coherent states (NLCSs) by introducing a more general nonlinear function and study their nonclassical properties, specifically the second-order correlation function [Formula: see text], Mandel parameter Q, squeezing, amplitude-squared squeezing and Wigner function of the optical field. The results indicate that the nonclassical properties of the new types of even and odd NLCSs crucially depend on the nonlinear functions. More concretely, we find that the new even NLCSs could exhibit the photon-bunching effect, whereas the new odd NLCSs could show the photon-antibunching effect. The degree of squeezing is also significantly affected by the parameter selection of these NLCSs. By employing various forms of nonlinear functions, it becomes possible to construct the NLCSs with diverse properties, thereby providing a theoretical foundation for the corresponding experimental investigations.

Quantum model in the context of six-level atom and deformed Lie algebra: Entanglement and statistical properties

In this work, we study the interplay between an atomic system with six levels configured in a cascade-type and one-mode fields in the framework of the f-coherent states. We explore the considered system dynamic properties under the effects of field nonlinearity and the number of photon transitions. In particular, we consider the quantum coherence, atomic upper level-occupation probability, and atom–field entanglement of a system when the effect of deformation is considered. Moreover, we analyze the dynamic of the Mandel parameter as a quantifier of the statistical properties of the field in the presence of deformation when the field is initially in coherent states.

Temporal evolution of a driven optomechanical system in the strong coupling regime

We obtain a time-evolution operator for a forced optomechanical quantum system using Lie algebraic methods when the normalized coupling between the electromagnetic field and a mechanical oscillator, G/ω m , is not negligible compared to one, i.e., the system operates in the strong-coupling regime. Due to the forcing term, the interaction picture Hamiltonian contains the number operator in the exponents, and in order to deal with it, we approximate these exponentials by their average values taken between initial coherent states. Our approximation is justified when we compare our results with the numerical solution of the number of photons, phonons, Mandel parameter, and the Wigner function, showing an excellent agreement. In contrast to other works, our approach does not use the standard linearized description in the optomechanical interaction. Therefore, highly non-classical (non-Gaussian) states of light emerge during the time evolution.

Calculation of the Mandel Parameter for an Oscillator-Like System Generated by Generalized Chebyshev Polynomials

Calculation of the Mandel Parameter for an Oscillator-Like System Generated by Generalized Chebyshev Polynomials

Bargmann transform and statistical properties for nonlinear coherent states of the isotonic oscillator

Abstract We construct a new class of nonlinear coherent states for the isotonic oscillator by replacing the factorial of the coefficients z n / n ! ${z}^{n}/\sqrt{n!}$ of the canonical coherent states by the factorial x n γ ! = x 1 γ . x 2 γ … x n γ ${x}_{n}^{\gamma }!={x}_{1}^{\gamma }.{x}_{2}^{\gamma }\dots {x}_{n}^{\gamma }$ with x 0 γ = 0 ${x}_{0}^{\gamma }=0$ , where x n γ ${x}_{n}^{\gamma }$ is a sequence of positive numbers and γ is a positive real parameter. This also leads to the construction of a Bargmann-type integral transform which will allow us to find some integral transforms for orthogonal polynomials. The statistics of our coherent states will also be considered by the calculus of one called Mandel parameter. The squeezing phenomenon was also discussed.

Investigation of the generalised Wigner–Dunkl harmonic oscillator and its coherent states

This study investigates the quantum mechanics of the harmonic oscillator in the presence of the Generalised-Wigner–Dunkl formalism based on creation and annihilation operators, which include also the reflection operator. We provide explicit results on the spectral properties of the Hamiltonian and an explicit form of the quantum propagator. Deformed coherent states are introduced and their non-classical properties such as photon statistics, Mandel parameter, and bunching or anti-bunching effect are studied.

Truncated generalized coherent states

A generalization of the canonical coherent states of a quantum harmonic oscillator has been performed by requiring the conditions of normalizability, continuity in the label, and resolution of the identity operator with a positive weight function. Relying on this approach, in the present scenario, coherent states are generalized over the canonical or finite dimensional Fock space of the harmonic oscillator. A class of generalized coherent states is determined such that the corresponding distributions of the number of excitations depart from the Poisson statistics according to combinations of stretched exponential decays, power laws, and logarithmic forms. The analysis of the Mandel parameter shows that the generalized coherent states exhibit (non-classical) sub-Poissonian or super-Poissonian statistics of the number of excitations, based on the realization of determined constraints. Mittag-Leffler and Wright generalized coherent states are analyzed as particular cases.

Phase space nonclassicality and sub-Poissonianity of deformed photon-added nonlinear cat states: algebraic and group theoretical approach.

In this Letter, we introduce four distinct classes of f-deformed photon-added nonlinear cat state. This would be achieved by recalling a nonlinear coherent states approach, as well as a particular class of Gilmore-Perelomov-type of SU(1,1) coherent state and a class of SU(2) coherent state. We then examine the role of photon addition and nonlinearity functions in the phase space structure and sub-Poissonianity of even, odd, and Yurke-Stoler nonlinear cat states. The effect of photon addition, which results in a π phase shift at the origin of the Wigner function toward negativity, interestingly enhances the nonclassicality by means of the Wigner function and Mandel parameter. Furthermore, owing to photon addition, we can observe a deformation in the Gaussian shape of the Wigner function, which may be found to be potentially useful in quantum noise reduction. Moreover, the deformation function shows a remarkable role in revealing the nonclassical behavior and can increase the depth and the domain of nonclassicality.

Nonclassical properties of a deformed atom-cavity field state

We analyse here a nonclassical state produced by an atom-cavity field interaction. The two-level atom is passed through the single-mode electromagnetic cavity field. By deforming the field operators and introducing nonlinearity to the classic Jaynes–Cummings model, we explore the system in respect of a nonlinear Hamiltonian. Assuming that the atom is in an excited state and the field is in a coherent state initially, the analytic expression for the state vector of the entire system state vector is obtained. With the help of the derived state vector, we calculate the photon number distribution, Mandel's parameter, Wigner function, anti-bunching, squeezing properties and Q function etc.

Engineering nonclassical SU(1,1) coherent states of light by multiphoton excitation

Quantum optical systems with nonclassical features play a vital role in the physical implementation of a large variety of quantum technologies, such as quantum metrology, quantum information processing, and quantum computation protocols, and hence are important to exploit the quantum advantage. In this work, we construct a general class of nonclassical coherent states (CSs) of light and present a scheme to enhance their nonclassicality by multiphoton excitation. In particular, using various optical realizations of Lie algebra, we construct CSs of light following Barut-Girardello formalism and then perform the multiphoton discrete excitation on these continuous-variable optical CSs. We investigate the nonclassical features by analyzing the photon-counting probability distribution, Mandel parameter, quadrature squeezing, and Wigner quasi-probability distribution. Our numerical results show that, for a particular set of parametric values, these multiphoton excited states exhibit sub-Poisson photon-counting statistics, quadrature squeezing, and negativity of Wigner distribution, which are indicators of nonclassicality. Moreover, it is shown that the nonclassical nature of these states gets enhanced as the photon-excitation number increases.

A Class of Non-Classicality and Non-Gaussianity of Photon Added Three-mode GHZ-type Entangled Coherent States

In this paper, We investigate three-mode photon-added Greenberger-Horne-Zeilinger (GHZ) entangled coherent states by repeatedly operating the photon-added operator on the GHZ entangled coherent states. The product of two Laguerre polynomials is demonstrated to be connected to the normalizing constant. The influence of the operation on the non-classical and non-Gaussian behavior of the GHZ entangled coherent states is investigated. Sub-Poissonian statistics, such as Mandel's parameter and the negativity of the Wigner function, show that non-classical properties can enhance GHZ entangled coherent states. Finally, the occurrence of the anti-bunching phenomena in this class of tripartite excited states is studied using the second-order correlation function.

Gazeau-Klauder coherent states in position-deformed Heisenberg algebra

In this paper, we present coherent states à la Gazeau-Klauder for a free particle in square well potential within position-deformed Heisenberg algebra . These states satisfy the Klauder’s mathematical requirement to build coherent states. Some statistical properties such as the probability distribution, the intensity correlation function and the Mandel parameter are calculated and analyzed. We find that these states are sub-Poissonian in nature. We also construct for these coherent states, the even cat states and we evaluate its Wigner function which analyses the quasiprobability distribution of these states. We graphically demonstrate that these states exhibit nonclassical behavior.

Effect of relativistic motion on superconducting quantum bits under decoherence

In the present manuscript, we consider a quantum system of two super-conducting (SC) qubits that move at relativistic speeds and each qubit coupled to a resonator mode (RM). Here, the relativistic motion of the SC-qubits results from the modulation of the time-varying coupling between the SC-qubits and the resonator for which the system resembles the rotating approximation and anti-Jaynes-Cummings (JC) dynamics. We study the time variation of some interesting current quantumness measures with respect to the time-varying coupling (TVC) considering von Neumann entropy, negativity and Mandel parameter. We illustrate the dynamical behavior of the SC-qubits–RMs entanglement, SC-qubit–SC-qubit entanglement and photon statistics of the RMs at relativistic motion in the absence and presence of dissipative environment.

Nonlinear interaction of a three-level atom with a two-mode field in an optomechanical cavity: Field and mechanical mode dissipations

In this paper we investigate the dynamics of f-deformed interaction (nonlinear atom-field coupling) of a three-level atom in V-configuration with a two-mode quantized field in the presence and absence of Kerr medium as well as the phonon and photon dissipations in an optomechanical cavity. We solve the associated time-dependent Schrödinger equation and arrive at the corresponding state vector at arbitrary time. In the continuation, we evaluate several nonclassical properties including atomic von Neumann entropy, atomic information entropy squeezing, sub-Poissonian statistics and atomic squeezing, numerically. Our numerical results show that, with the parameters at our disposal, we can adjust the above-mentioned properties according to our purposes. For instance, significant amount of von Neumann entropy may be achieved, in the linear and nonlinear atom-field coupling, without or even with considered dissipations. However, atomic information entropy squeezing can be observed only in the presence of nonlinear atom-field coupling by tuning the proper values of Lamb-Dicke parameter. Atomic squeezing can be seen in the presence or absence of linear and nonlinear atom-field coupling. Negative values of Mandel parameter, showing the sub-Poissonian statistics as the nonclassicality of the field can be observed with and without nonlinear atom-field coupling, however, the presence of Lamb-Dicke nonlinearity can make this effect more visible. Unless the atomic information entropy squeezing, in all above-mentioned physical phenomena stability of the evaluated parameters can be accessible via choosing appropriate parameters containing Lamb-Dicke parameter, Kerr effects, dissipation parameters, laser pumps and photon-phonon coupling.

Predication and Photon Statistics of a Three-Level System in the Photon Added Negative Binomial Distribution

Statistical and artificial neural network models are applied to forecast the quantum scheme of a three-level atomic system (3LAS) and field, initially following a photon added negative binomial distribution (PANBD). The Mandel parameter is used to detect the photon statistics of a radiation field. Explicit forms of the PANBD are given. The prediction of the Mandel parameter, atomic probability of the 3LAS in the upper state, and von Neumann entropy are obtained using time series and artificial neural network methods. The influence of probability success photons and the number of added photons to the NBD are examined. The total density matrix is used to compute and analyze the time evolution of the initial photonic negative binomial probability distribution that governs the 3LAS–field photon entanglement behavior. It is shown that the statistical quantities are strongly affected by probability success photons and the number of added photons to the NBD. Also, the prediction of quantum entropy is achieved by the time series and neural network.

Photon statistics and non-local properties of a two-qubit-field system in the excited negative binomial distribution

In this paper, a quantum scheme for a two-qubit system (2QS) and field initially prepared in the excited negative binomial distribution is presented. The field photon statistics is detected from the evolution of the Mandel parameter, while the evolution of von Neumann entropy detects the nonlocal correlation between the 2QS and radiation field. The concurrence is used to detect the qubit-qubit entanglement during the time evolution. The dynamical properties of single-qubit and two-qubit quantum Fisher information are investigated. We visualize the number of photon excitations on the field in negative binomial states with influence of photon success probability. A connection is provided between the dynamical behaviors of these statistical quantities. We have found that the proposed quantities are strongly influenced by the number of excited photons of the field in negative binomial states and photon success probability.

Effects of Energy Dissipation and Deformation Function on the Entanglement, Photon Statistics and Quantum Fisher Information of Three-Level Atom in Photon-Added Coherent States for Morse Potential

The present research paper considers a three-level atom (3LA) that interacts with a field mode primarily in a photon-added coherent state of Morse potential (PACSMP). The dynamics of entanglement, the photon statistics, and the quantum Fisher information are investigated. The statistics of field photons are discussed by evaluating the Mandel parameter. We check the influence of the energy dissipation and intensity-dependent function. Finally, we detect the relationship between the entanglement, the field’s nonclassical characteristics, and atomic quantum Fisher information throughout the evolution of time. The findings illustrate the important role of the number of added photons and CSMP in affecting the entanglement’s time evolution, the quantum Fisher information, and the Mandel parameter. Based on the obtained results, we reached significant physical phenomena, including the sudden birth and death of the nonlocal correlation between atom-Morse potential field structures.

Quantum-optical description of photon statistics and cross correlations in high-order harmonic generation

We present a study of photon statistics associated with high-order harmonic generation (HHG) involving one-mode and intermodal correlations of the high harmonic photons. The aim of the paper is to give insight into the nonclassical properties of high-order harmonic modes. To this end, we use a simplified model describing an elementary quantum emitter: the model of a two-level atom. While the material system is extremely simplified in this description, the conclusions and the methods may be generalized for more complex cases. Our primary interest is an effective model of HHG in which the exciting pulse is classical and the harmonics are quantized, although we touch upon the more generalized, fully quantized model as well. Evolution of the Mandel parameter, photon antibunching, squeezing, and cross correlations are calculated. Results imply that with respect to a single quantized emitter, nonclassicality of the harmonics is present: sub-Poissonian photon statistic and squeezing can characterize certain optical modes, while strong anticorrelation can also be present.