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• Quantum phenomena. • Quantum steering. • Asymmetry and symmetry interaction. • Liouville-von Neumann equation. • Parameter estimation theory. The quantum steering and quantum Fisher information (QFI) for two qubits in the presence of qubits interaction and dephasing coupling is studied. We show how the dynamics of the quantumness measures can be influenced by the qubits interaction considering symmetry and asymmetry interaction between the environment and the qubits. We find that protection of the steering and enhancement of the parameter estimation precision (PEP) can be made through a proper choice of the quantum model parameters. Finally, we display the relationship between the fidelity, steering and QFI during the dynamics. [ABSTRACT FROM AUTHOR]

By considering two kinds of non-Markovian (NM) environments, the dynamical behavior of quantum steering, Bell nonlocality and coherence of a system of two atoms initially immersed in a vacuum has been studied. In this context, the cases of a cavity little off-resonance with the atomic transition frequency and non-perfect photonic band-gap (NPPBG) has been considered. The control and preservation of the quantumness measures is discussed in terms of the physical parameters. Furthermore, the situations for which the atoms state is steerable with the presence of Bell nonlocality and coherence has been illustrated. Finally, the monotonic dependence among the quantumness measures is displayed with respect to the model parameters. [ABSTRACT FROM AUTHOR]

In this work, we examine the process of the quantum transfer of energy considering time-dependent dipole-dipole interaction in a dimer system characterized by two-level atom systems. By taking into account the effect of the acceleration and speed of the atoms in the dimer coupling, we demonstrate that the improvement of the probability for a single-excitation transfer energy extremely benefits from the incorporation of atomic motion effectiveness and the energy detuning. We explore the relevance between the population and entanglement during the time-evolution and show that this kind of nonlocal correlation may be generated during the process of the transfer of energy. Our work may provide optimal conditions to implement realistic experimental scenario in the transfer of the quantum energy. [ABSTRACT FROM AUTHOR]

In present manuscript, we build the photon-added deformed spin coherent states (PA-DSCSs) according to deformed spin algebra (DSA). We present the way for solving the unity operator problem and we give the solution for some particular cases. The obtained states are developed through the Holstein-Primakoff (HP) realization of the DSA. The statistical features of the obtained coherent states are examined through the variation of the Mandel's parameter. By using the PA-DSCSs, we investigate the bipartite entanglement with respect to different parameters of these states. [ABSTRACT FROM AUTHOR]

We study the coherence and quantum correlations for a system consisting of two interacting qubits under the effect of a common environment, where the system of qubits has the dephasing coupling with its surrounding. We study the dynamical behavior of the quantumness measures when the influence of the qubits' interaction on the dephasing is analyzed. We display the effect of the qubit–qubit interaction and qubits–environment interaction on the measures considering the case of symmetry and asymmetry interaction between the qubits and environment. Finally, we explicitly illustrate the relation between the coherence and quantum correlations and show that quantum coherence and correlations can be preserved during the dynamics. • Quantum dynamics. • Symmetry and asymmetry interaction. • Qubit–qubit interaction. • Qubits–environment interaction. • Coherence and quantum correlations. [ABSTRACT FROM AUTHOR]

• Quantum system of two superconducting qubits under the effect of Josephson energy and temperature. • Quantum quantifiers can be controlled by appropriate selection of the Josephson energy and temperature. • Coherence based on the degree of mixedness in the superconducting qubit state is investigated. • Enhance, preserve, and maintain the level of coherence in the existence of temperature variations are determined. In a model consisting of two superconducting charge qubits (SC-Qs), we study how the Josephson energy (JE) and temperature have an influence on the coherence, the degree of mixedness, and the nonclassical correlation. In this example, we show how the quantumness metrics change depending on the JE and the temperature. We also show that the number of quantifiers can be controlled by appropriate selection of the JE of the SC-Q and temperature effect. Additionally, we determine the optimal conditions required to enhance and preserve the coherence and maintain the level of coherence in the existence of temperature variations. We observe important quantum phenomena, i.e., coherence trapping and the quantum correlation trapping. Furthermore, we explain the variations in the coherence based on the degree of mixedness in the superconducting qubit state. [ABSTRACT FROM AUTHOR]

• Tavis–Cummings model. • Kerr medium and Ising interaction. • Interaction between the atoms and field. • Quantum dynamics. • Entanglement and coherence in two level atom systems. In the present manuscript, we investigate qualitatively the quantum entanglement and coherence in two atoms coupled to a quantized field in the existence of Kerr medium and Ising interaction. We explore the effects of the atom–atom (A–A) interaction and field nonlinearity on the dynamics of quantumness measures by examining the A–A concurrence, von Neumann entropy, l 1 norm coherence and Mandel's parameter. We also illustrate the relations between the information quantifiers in the presence and absence of field dissipation. [ABSTRACT FROM AUTHOR]

In this paper, we develop the model of the four-level double Raman pairs by exploiting the required optimal conditions for this system that are feasible with real experimental realization. We investigate qualitatively the entanglement, statistical properties, and geometric phase for the pair of Stokes and anti-Stokes photons in the presence of the time-dependent coupling effect. We show that these quantifiers are very sensitive to the change of the Rabi frequency and time, exhibiting substantial phenomena that are depending on the kind of coupling between the atom and photons. Finally, we explore the relationship between the quantum quantifiers in terms of the physical parameters with and without time-dependent coupling effect. [ABSTRACT FROM AUTHOR]

The quantitative description of the quantum correlations between each two-level system in a two-atom system and the coherent fields initially defined in a coherent state in the framework of power-law potentials (PLPCSs) is considered. Specifically, we consider two atoms locally interacting with PLPCSs and take into account the different terms of interactions, the entanglement and quantum discord are studied including the time-dependent coupling and photon transition effects. Using the monogamic relation between the entanglement of formation and quantum discord in tripartite systems, we show that the control and preservation of the different kinds of quantum correlations greatly benefit from the combination of the choice of the physical quantities. Finally, we explore the link between the dynamical behavior of quantum correlations and nonclassicality of the fields with and without atomic motion effect. [ABSTRACT FROM AUTHOR]

• Interacting superconducting qubits. • Influence of temperature and energies. • Entropy squeezing and quantum measurement. • Superconducting systems for new applications in quantum technologies. We investigate the effects of temperature on quantum Fisher information (QFI), fidelity, and entropy squeezing in two interacting superconducting qubits (SCQs). We show how the variations in these quantum quantifiers may be controlled by carefully selecting the model's physical parameters (PPM). We obtain a trapping phenomena for Fisher information, allowing us to improve the QFI and retain the amount of information while also preserving it from information loss due to temperature impacts. We evaluate the fidelity of the SCQ to explain the dynamic aspects of the QFI in relation to the PPM. Furthermore, we examine the influence of the PPM on the variation in the squeezing entropy for SCQs. The results indicate how, in terms of quantum measurement theory, the system under consideration might be valuable in enabling the realization of experiments under optimal conditions. [ABSTRACT FROM AUTHOR]

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. • The proposed quantum system of two super-conducting (SC) qubits that move at relativistic speeds and each qubit coupled to a resonator mode (RM) is introduced. • 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. • The time variation of some interesting current quantumness measures with respect to the time-varying coupling considering von Neumann entropy, negativity and Mandel parameter is investigated. • 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 was illustrated in detail. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

• Emission spectrum of a two-level coupled to generalized squeezed states. • Atom-field system in the context of multi-photon transition. • Effect of the squeezed parameter, transition parameter and half-band-width of the spectrometer. • Field purity of the atom-field state Equation of motion without rotating wave approximation. The present study investigates the transient spectrum (TS) of a two-level system that interacts with a generalized squeezed state without using the rotating wave approximation (RWA). We consider the purity of the optical field, which is developed in a generalized squeezed state, utilizing the linear entropy. The analytic expressions of the TS and field purity (FP) of the bipartite system are evaluated. Moreover, the study exhibits the influence of the squeezed parameter and some photons transition on the TS and FP. We obtain that the control of the FP may be generated based on an adequate choice of the photons transition and squeezed parameter. Such results can be utilized in the understanding and development of various tasks of quantum physics and optics. [ABSTRACT FROM AUTHOR]

• Qubit systems including classical driving field. • Time-dependent effect on the comportments of the quantum quantifiers in quantum technologies. • Markovian and non-Markovian dynamics. • Quantum coherence dynamics. • Dynamics of classical and quantum correlations • Effect of pure and mixed states. By considering an exactly solvable model for a driven two non-interacting qubits, each coupled to a bosonic environment with zero temperature, under the non-Markovian dissipative process, we study the variation of coherence and correlations in terms of different physical parameters. We show the influence of the external classical driving field as well as the initial quantum states. Moreover, we highlight the relationship between the coherence, single-qubit population, and correlations according to the physical parameters of the whole system. We reveal that the preservation and enhancement of coherence and correlations may occur by adjusting the strength of the classical driving field, initial states, and non-Markovian effects. [ABSTRACT FROM AUTHOR]

• Emission spectrum of a two-level coupled to a nonlinear bosonic field. • Atom-field system in the context of parity deformed Jaynes-Cummings model. • Effect of the deformed parameter, detuning and half-band-width of the spectrometer. • Geometric phase of the atom-field state with parity deformed Jaynes-Cummings model. • Equation of motion without rotating wave approximation. The emission spectrum of a qubit (two-level atom) system that interacts with a field in the framework of parity deformations is investigated in this paper. The model consists of a qubit coupled to a single-mode field within the parity deformed Jaynes-Cummings model (PDJCM) based on the λ -analog of the quantum harmonic oscillator algebra. We numerically evaluate the atomic emission spectrum (AES), by considering the influence of the deformed parameter and half-band-width of the spectrometer. Moreover, the dependence of the spectrum peaks on the detuning parameter is discussed. Finally, we study the variation of the geometric phase of the whole system state modelled by the PDJCM in terms of the main physical parameters. [ABSTRACT FROM AUTHOR]

• Solid state systems including superconducting qubits. • Time-dependent effect on the comportments of the quantum quantifiers in superconducting quantum technologies. • Superconducting qubits coupled to mode fields in a circuit quantum electrodynamics setup. • Detuning and dipole-dipole effect on the dynamical behavior of the quantum quantifiers. The engineering of Kerr and time-dependent coupling interactions is of great attention for treating quantum information in quantum systems and for investigating the collective behavior of large numbers of interacting particles in a cavity-qubit network. In this manuscript, we investigate the time evolution of the entanglement and some nonclassical properties of two superconducting qubits interacting with a single-mode field in the presence of a Kerr-like medium and dipole–dipole interaction without and with time-dependent coupling effect. We show that a slight alteration in the interaction, detuning, and Kerr parameters might cause a change in the entanglement of subsystem states during the evolution. By taking into account the influence of the different physical parameters, we show the statistical distributions produced in the photons of the single mode field through the calculation of the Mandel's parameter. Finally, we find that the time-dependent Mandel's parameter not only provide the statistical properties of the field, but also include the information of quantum entanglement for the subsystem states. [ABSTRACT FROM AUTHOR]

In this manuscript, we study the deformed optical tomography for excited coherent states associated to deformed Heisenberg algebra. By using the numerical solution of the recurrence relation, we evaluate the eigenstates of the deformed quadrature operator and give the exact analytical formula of the optical tomogram for the photon-added deformed coherent states (PA-DCSs) and photon-added deformed cat coherent states (PA-DCCSs). Finally, we display the variation of the excited coherent states in the terms of the different physical parameters defined in the coherent states and show how these parameters affect the shape of the optimal tomography. [ABSTRACT FROM AUTHOR]

We study the nonclassical and nonlocal properties for atom-field systems in the context of Pöschl-Teller potential. Using the coherent states for Pöschl-Teller potentials, we propose a Jaynes Cummings model that characterizes the interaction among two-level atoms and fields with this kind of potential. After solving the motion equation, we examine the dynamical change of atomic inversion, entanglement, fidelity, and squeezing phenomenon with respect to initial parameter values. We show how the quantities can be controlled through the proper choice of the potential parameters. Finally, we give the connection among the quantum quantifiers for both whole system and subsystems during the evolution. [ABSTRACT FROM AUTHOR]