In this paper, we introduce a modified class of correlated coherent states. These states are realized during the consideration of a new model which represents the interaction between a two-level atom and two electromagnetic fields injected simultaneously within a cavity. By using the transition amplitude we have managed to establish the relationship between the usual coherent states and the modified states. The phenomenon of squeezing and the variances of the photon number sum and difference are discussed. It has been shown that the mean photon number controls the value of the correlation. Furthermore, our discussion on the quasi-probability distribution functions (the Wigner and Q-functions) shows that both functions are sensitive to the change in the ratio of the field modes as well as the coupling parameter λ1.
In this paper, we introduce a modified class of correlated coherent states. These states are realized during the consideration of a new model which represents the interaction between a two-level atom and two electromagnetic fields injected simultaneously within a cavity. By using the transition amplitude we have managed to establish the relationship between the usual coherent states and the modified states. The phenomenon of squeezing and the variances of the photon number sum and difference are discussed. It has been shown that the mean photon number controls the value of the correlation. Furthermore, our discussion on the quasi-probability distribution functions (the Wigner and Q-functions) shows that both functions are sensitive to the change in the ratio of the field modes as well as the coupling parameter λ1.
We consider a cavity field state, which is created by the atom-cavity field's interaction in the presence of a driven field. The two-level atom passes through the cavity and is driven by a weak classical field. A photon number dependent Stark shift is induced by the atom's dispersive interaction with the cavity field. When the atom is in excited state ∣a⟩, the output cavity field thus obtained is taken into consideration. With the help of the state evaluated, we investigate different statistical properties such as photon number distribution, Wigner function, Mandel's Q parameter and squeezing.
A quantum optics model is considered where the cavity field interacts with two coupled atoms. The time-dependent wave function is obtained and used to derive the density matrix from which we discussed some statistical properties for the present system. The atom-atom entanglement, atoms-cavity entanglement, entropy and variance squeezing, the Pegg-Barrnet phase and the fidelity are discussed with the effects of the initial conditions, atom-atom coupling and the detuning parameter displayed. It is shown that an increase in the value of the atom-atom coupling parameter leads to an increase in the degree of entanglement. Numerical results show that under some conditions the phenomena of entanglement and the collapses and the revivals emerge. Nonclassical properties are demonstrated by means of the field quantum statistical characteristics, such as photon-number distribution, Husimi, Wigner and Glauber-Sudarshan quasidistributions and the corresponding variances.
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 QM parameter, Wigner function, anti-bunching, squeezing properties and Q function etc.
We consider the case that one of the two initially entangled V-type three-level atoms is injected into a two-mode cavity and resonantly interacting with a two-mode field initially in a SU(2) coherent state.Nonclassical properties of the two-mode correlated field are investigated numerically.The influences of the state-selective measurement of the atom outside the cavity,the total photon number of the two modes,and the partition parameter on the difference squeezing,the Cauchy-Schwarz inequality,the mode-correlation properties,and the photon number distribution are discussed.The results indicate when the state-selective measurement is performed on the atom outside the cavity or the total photon number is increased,the difference squeezing and the sub-Poisson distribution of the photon number of mode a is distinctly enhanced,but the anti-correlation between the two modes is distinctly reduced.
Cavity quantum electrodynamics is the intersection of quantum physics and microcavity optics research. In this paper, we presented a two-mode cavity coupled to a classical field driven by N three-level atoms to prepare entangled coherent states based on cavity QED. In this scheme, we adopt the interaction between the three-level atoms and the two-mode optical cavity, The initial state of one optical field is an odd-even coherent state, while the initial state of another optical field is a coherent state. After considering the time evolution of the initial states with the system, we obtained the specific form of the time evolution of the quantum states and prepared the entangled coherent state successfully. We discussed and analysed some of the nonclassical properties of the optical field and quantum states, including the second-order correlation function and the Wigner function. The results show that when calculating the second-order correlation function, the photons are found to exhibit a sub-Poisson distribution at some points in time. In addition, when observing the Wigner function of the quantum states evolving with time, it is found that there is a negative part of the Wigner distribution at some moments, which implies that the quantum state exhibits nonclassical properties at these certain moments.
We investigate nonclassical properties of a state generated by the interaction of a three-level atom with a quantized cavity field and an external classical driving field. In this study, the fields being degenerate in frequency are highly detuned from the atom. The atom interacts with the quantized field in a dispersive manner. The experimental setup involves a three-level atom passing through a cavity and interacting dispersively with the cavity field mode. Simultaneously, the atom interacts with an external classical field that is in resonance with the cavity field. The three-level atom can enter the cavity in one of the bare states [Formula: see text], [Formula: see text] or [Formula: see text] or in a superposition of two of these states. In this paper, we consider superposition of [Formula: see text] and [Formula: see text]. In our analysis, we focus on the statistical properties of the cavity field after interacting with the atom. The state vector [Formula: see text] describes the entire atom–field system but we analyze the properties of the cavity field independently neglecting the atomic component of the system. For this the atom part is traced out from [Formula: see text] to acquire the cavity field state only, denoted by [Formula: see text]. We evaluate different nonclassical measures including photon number distribution, Mandel’s [Formula: see text] parameter, squeezing properties [Formula: see text] and [Formula: see text], Wigner distribution, [Formula: see text] function, second-order correlation function [Formula: see text], etc. for the obtained cavity field state.