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We investigate the dynamics of measurement-induced nonlocality (MIN) with two spins in an ideal single-mode optical cavity. The two-spin entangled states are generated firstly under the photon coherent state assumption by means of the variational method. The time evolution of MIN is then examined based on the derived analytical expressions of the reduced density operator of two spins. It is shown that MIN remains in its upper bound all the time and independent of the average photon number of the coherent field when the two spins are initially in the singlet state, which just is the eigenstate of our model. However, for the initial general two-spin entangled states of antiparallel and parallel spin polarizations, MIN strongly depends on the average photon number and initial angle parameters. We provide a detailed analysis of MIN dynamics by the numerical calculation, and reveal some significant results. [ABSTRACT FROM AUTHOR]

We study the dynamic creation of two different geometric quantum discords (GQDs) defined, respectively, via the Hilbert–Schmidt norm (GQD-2) and trace norm (GQD-1) between the two qubits, which are prepared initially in a zero discord two-qubit X-shape state, and subject to a two layers environment that consists of a lossy cavity coupled to the W-coupled lossy cavities. We find that the GQD-2 and GQD-1 exhibit oscillatory behavior in the regime of the strong coupling between the qubit and first-layer cavity environment. And in both the weak and strong coupling regimes, for the greater the number of cavities in the second-layer environment, the GQDs reach their peak value in a larger time and go to zero more slowly. But in the qubit–cavity coupling, the coupling between two nearest neighbor cavities and the decay rate of cavities in the second-layer environment have the opposite effect on the GQDs. Furthermore, the maximum value of GQDs remains unchanged and the steady value increases, or they both decrease, depending on the threshold value of coupling between the two layers environment. Finally, we propose an effective strategy to improve the GQD-2 and GQD-1 by using local filtering operation. [ABSTRACT FROM AUTHOR]

We investigate the dynamic creation of quantum correlation and entropic uncertainty relation (EUR) in a system of two non-interacting qubits, which are initially prepared in a classically correlated state and subject to the independent radiation in an isotropic or anisotropic photonic bandgap (PBG) crystal environment. It is shown that the detuning condition and environmental structure play a crucial role in controlling the emergence of geometric quantum discord (GQD) and one-norm GQD. In addition, the remarkable similarities and differences for quantum correlation in two PBG environments are also analyzed in detail. Finally, we explore the time evolution of EUR in our model under the influence of PBG environment and present some interesting results. [ABSTRACT FROM AUTHOR]