Enhancement of stationary state quantum discord in Tavis–Cummings model by nonlinear Kerr-like medium

We investigate the influence of nonlinear Kerr-like medium and dipole-dipole interaction on the dynamics of quantum discord in Tavis–Cummings model with phase decoherence. We show that in the resonance case (i) atom-field quantum discord rapidly decays with phase decoherence and doesn't exist the stationary state quantum discord, but the stationary state quantum discord appears if we choose the suitable values of Kerr coefficient χ and dipole–dipole interaction Ω, (ii) the quantum discord of two atoms survives in the stationary state and the amount of stationary state quantum discord could be improved by adjusting the values of χ and Ω. In the non-resonance case, the arbitrary bipartite quantum discord of the system could not be completely destroyed by the phase decoherence and can be improved by applying nonlinear Kerr-like medium and dipole-dipole interaction.

Research highlights
► We investigate the influence of nonlinear kerr-like medium and dipole-dipole interaction on the quantum discord dynamics in Tavis–Cummings model with phase decoherence.
► In the resonance case, applying the nonlinear kerr-like medium and dipole-dipole interaction, the stationary state atom-field quantum discord can be obtained and the stationary state quantum discord between two atoms can be improved.
► In the non-resonance case, the arbitrary bipartite stationary quantum discord of the system can be improved by by adjusting the values of kerr coefficient and dipole-dipole interaction.