Abstract
In the present work, we examine qualitatively the entanglement and parameter estimation in a two superconducting qubits (SC-qubits) coupled to a nonlinear field in the existence of time-varying coupling. We show the effects of the nonlinearity of the field and time-varying coupling on the evolution of such quantities of current interests by considering the von Neumann entropy, entanglement of formation and quantum Fisher information (QFI). Moreover, we explain the relationship between the information quantifiers during the dynamics. The obtained results can suggest new prospects to explore and understand the nonlinearity phenomena on the behaviour of the information quantifiers in SC-qubits.
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