Quantum information of a three-level atom in one-dimensional photonic bandgaps

摘要

In this paper a novel analytical method is applied to the problem of investigating the fidelity and linear entropy of a three-level system in the presence of a photonic band gap. Using this analytic solution, we conclusively calculate the fidelity and linear entropy, related particularly to the entanglement phenomena. We demonstrate how fluctuations in the fidelity and linear entropy are effected by the presence of the photonic-band-gap. The outcomes are illustrated with numerical simulations applied to GaAs. It is found that the time evolution of the lower bound of the linear entropy systematically captures the corresponding collapse and revival features. Our work also sheds light on quantum information storage and processing with multi-level atoms.