Statistical Properties of the Odd Binomial States with Dynamical Applications

In this paper we investigate the odd binomialstate, which interpolates between odd number and oddcoherent states. We discuss the statistical propertiesof the Glauber second-order correlation function and squeezing phenomena (normal squeezing andamplitude-squared squeezing). The phase properties inPegg-Barnett formalism are considered, and thequasiprobability distribution functions are examined.The dynamics of the Jaynes-Cummings model and theresonance fluorescence are also discussed.     

Direct Observation of Dissipation in Dynamical Search Algorithm using Transmon Qubits

Following recent work [Fortschritte der Physik 66, 1700080 (2018)], the dissipation effect of the dynamical quantum search algorithm (DQSA) is investigated. Such an algorithm is realized with the interaction of multi superconducting transmon qubits inside a 3D bus cavity. The dissipation of such system is caused by managing the sensitivity to charge noise via tuning the qubit frequency by employing Josephson energy. The probabilities of marked and unmarked states for the present algorithm have been calculated analytically and numerically. Such probabilities of marked states are sensitive to any change in the dissipation parameter. A deficiency causes the dissipation for the marked states, and that deficiency is added to the unmarked states. It is interesting to mention that one of the datasets at large dissipation rates gives an observation of the marked states probabilities which is related to the decoherence free subspace. It is predicted that the algorithm can be successfully implemented in the current experiments.     

Generalized Trio Coherent States

Generalized trio coherent states are made by superposing a number of trio coherent states. They possess inherent nonclassical properties such as sub-Poissonian distribution and violation of Cauchy-Schwarz inequalities. Their phase distribution in the framework of the Pegg and Barnett theory is discussed. We study the interaction of the radiation field prepared in a generalized trio coherent state with an atom in a superposition coherent state in the rotating wave approximation. We investigate the time dependence of the sub-Poissonian distribution and the violation of Cauchy-Schwarz inequalities for such a system. General conclusions reached are illustrated by numerical results.     

Entropies and Entanglement for Initial Mixed State in the Multi-quanta JC Model with the Stark Shift and Kerr-like Medium

In this paper, we study the time evolution of the entropies and the degree of entanglement in the mixed state for a multi-quanta JC model taking into consideration Stark shift and Kerr-like medium effect, we use a numerical method to investigate the time evolution of the partial entropy of the atom and field subsystem. This is done in the framework of the multi-quanta presses JC model with both the Stark shift and Kerr-like medium effect added. Furthermore, we examine the effect of the superposition states and a statistical mixture of coherent states as an initial field on the entropies and entanglement. Our results show that the setting of the initial state play an important role in the evolution of the sub-entropies and entanglement.     

Influence of phase damping on the entanglement for the damped JC model in the pure and mixed states

In this article, we investigate the effects of phase damping on the temporal evolution of different entanglement measurements and the amount of entanglement for the damped Jaynes-Cummings model. The master equation is solved for any initial state in the two-level atom. Superpositions of two coherent states (π/2 or π out of phase) and their statistical mixture state are taken as initial states when a phase-damped cavity is taken into account.     

Purity and Correlation of a Cavity Field Interacting with a SC Charge Qubit with a Lossy Cavity

A single-mode microwave cavity field, coupled to its reservoir, interacting generally with a superconducting charge qubit is considered. Using a certain canonical transformation for the qubit states, the system is transformed into the usual Jaynes-Cummings model. The solution of the master equation of this system, in the case of a high-Q cavity is obtained. The temporal evolution of the population inversion is explored. The effects of cavity damping on the purity of the qubit, the field and the global system state are studied. It is found that due to the coupling between the system and environment, the purity is lost. The entanglement is compared with total correlation. It is found that, with the damping parameter, the asymptotic value of the correlation measure is not null, since the global system evolves to a classically correlated state. The negativity is used as an indicator of the degree of entanglement between the qubit and the field. The results indicate the sensitivity of these aspects to change of the damping parameter.     

New features of Wehrl entropy and Wehrl PD of a single Cooper-pair box placed inside a dissipative cavity

In this paper, we discuss the coherence of a single Cooper-pair box irradiated by a single-mode quantized field in a coherent state inside a phase-damped cavity. Analytic results under certain parametric conditions are obtained, by means of which we analyze the influence of dissipation on the Wehrl entropy and Wehrl phase distribution. An interesting relation between the coherence and the dissipation effect is observed.     

Generation and some non-classical properties of a finite dimensional pair coherent state

A new state of electromagnetic field is introduced. It is a type of the correlated two-mode states but in finite dimensions. Based on the resonant ion-cavity interaction, we propose a scheme to generate these states revealing their connection with the converter type of interaction and investigate some of their nonclassical properties.     

Entanglement of Two Coupled Atoms in the Presence of a Time-Dependent External Magnetic Field

We study the problem of a time-dependent nonuniform magnetic field in the Heisenberg chain. We consider two cases: a single two-level atom and N-level atoms affecting by the magnetic field. We obtain the wave function and use it for calculating the expectation values of the dynamical operators, more precisely, the atomic inversion, in order to study the phenomena of revivals and collapses. Furthermore, we obtain the expectation value of other operators of the SU(2) group and discuss the phenomenon of squeezing. We show that the phase angle η and the detuning parameter δ are the most substantial parameters of the model under consideration.     

Maximally Entangled SU(1,1) Semi Coherent States

In this paper, we consider a special type of maximally entangled states namely by entangled SU(1,1) semi coherent states by using SU(1,1) semi coherent states(SU(1,1) Semi CS). The entanglement characteristics of these entangled states are studied by evaluating the concurrence.We investigate some of their nonclassical properties,especially probability distribution function,second-order correlation function and quadrature squeezing . Further, the quasiprobability distribution functions (Q-functions) is discussed.