Auto- and Cross-Correlation-Functions as entanglement quantifiers in semiconductor microcavities

Abstract: The dynamics of the exciton-photon entanglement, in a semiconductor microcavity is analyzed. Finding a closed analytical expression for the time evolution of the concurrence. Using as model two coupled, quantum oscillators with detuning between them. Supposing that the system is at a temperature closer to zero. And that the quantum state of the system, remains in the one excitation sector of the total Hilbert space. The former theoretical setup, describes the excitons coupled to the photons in the microcavity accurately, for a system with ultra low density of excitons. We remark in first place, that our closed expression for the concurrence dynamics. Enable us to establish a good analytical criterion, to determine the coupling dynamical regime, in which the system is. Even more, we show that our criterion, is in good agreement with typically accepted, experimental signatures for strong, and wake coupling regimes. Finally we present theoretical evidence, suggesting that the entanglement between the exciton and the photon. Can be measured in experiments, v\'ia the cross correlation contribution, to the time resolved spectra of the system.