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This study investigates the quantum heat correlations associated with the quantum Otto machine, considering the discrete sides of the Lipkin-Meshkov-Glick model as the working medium in the presence of a magnetic field and a symmetric cross interaction. The eigenenergy and occupation probabilities of two-sided and three-sided spin interactions are determined at thermal equilibrium. The results reveal symmetrical heat correlations around the coupling of the symmetric cross interaction, regardless of whether the working medium adopts anisotropic XY, Ising model, or mixed ferromagnetism. The work done by two or three sides of the mixed ferromagnetic working substance exhibits symmetry but with different maximum bounds. Furthermore, the efficiency of the two-sided mixed ferromagnetism model improves as the exchange parameter increases, while the maximum efficiency of the anisotropic XY model is lower compared to the efficiency of the Ising model and mixed ferromagnetism. It is also highlighted that a quantum heat engine or refrigerator can be generated by controlling the system's anisotropy parameter using a three-sided spin interaction. [ABSTRACT FROM AUTHOR]

The interaction of a 2-level atom with a time-dependent cavity field (two-photon non-degenerate transitions) in the parametric amplifier-type is considered. Using the integrability conditions, taking into account the phase and coupling, a general solution of the model is obtained through the Schrödinger equation. The effects of the functional dependence of the coupling and the initial state of the 2-level atom on atomic inversion, the degree of entanglement, entropy squeezing are investigated. It is shown that the acceleration term plays an important role in controlling the functions behavior of the considered quantities. [ABSTRACT FROM AUTHOR]

We discuss the effect of damping on a quantum system specifically described by the su(1, 1) Lie algebra and interacting with a two-level atom in the presence of external classical su(1, 1) terms. We obtain the numerical solution of the associated differential equations and discuss in detail several statistical aspects, atomic inversion, squeezing phenomena, and negativity. In addition, we analyze the effect of the decay parameter and the external classical su(1, 1) terms on the population inversion and purity. Finally, we examine the entropy squeezing and the degree of entanglement for some values of the damping and detuning parameters. [ABSTRACT FROM AUTHOR]

An extended analytic approach is considered for optical Bloch equations in the two level atom interacting with laser light. The separation approach of coupled differential equations is always possible with a sequence of special transformation into the Riccati nonlinear differential equation. The conditions that permit an exact solutions of three coupled system are extracted in a natural manner. The case of sodium atom moving along the axis of a monochromatic wave is treated in some details including a discussion on the radiation pressure forces exerted by laser light in the transient regime. [ABSTRACT FROM AUTHOR]