Quantum effects induced by two classical fields in a coherent cavity field containing two two-level atoms

The paper derives an exact solution for a two-qubit system coupling to a quantized cavity field driven by two different types of external fields when the cavity is initially in a coherent field state. The two-qubit quantum coherence via the Jensen–Shannon divergence and the two-qubit entanglement via the negativity are investigated under the effects of the physical parameters. The results are depicted that, the generated two-qubit effects depend on the external-qubit and the external-field detunings as well as the initial cavity coherent intensity. It is found that the increase of the parameters of the initial coherent states, the detuning between the cavity field and the external classical field, and the detuning between the qubit and the external classical fields are played a key role in the dynamics of the population inversion and the generated entropic qubit-cavity entanglement. The oscillation amplitudes of the atomic population can be improved when the classical-field detuning is equal to the qubit detuning, and they can be weakened dramatically when the qubit detuning is smaller than the classical-field detuning. The qubit-cavity entanglement can be improved when the classical-field detuning is larger than the qubit detuning, and vice versa.