A comparative study of entanglement amplification in a nondegenerate three-level cascade laser employing various inseparability criteria

摘要

A detailed comparison among the exhibited nature of entanglement of the cavity radiation of the nondegenerate three-level cascade laser when different inseparability criteria are employed is presented. Although the achievable degree of entanglement is generally found to vary with the applied inseparability criteria, there are cases for which more than two of the applied criteria lead to a significant degree of entanglement for certain parameters. Particularly, the procedures following from the criterion of Duan-Geidke-Cirac-Zoller and logarithmic negativity predict a similar pattern of entanglement except when the atoms are initially prepared in a maximum atomic coherent superposition. In the same manner, in relation to the absence of interatomic interaction, the Hillery-Zubairy and Cauchy-Schwarz inequalities virtually lead to a similar degree of entanglement. Since an appreciably large degree of entanglement is shown to be realizable using various criteria, there is no doubt that this quantum system can be utilized as a viable source of entangled light.