Nonclassicality criteria: Quasiprobability distributions and correlation functions

Abstract

We use the exact calculation of the quantum mechanical, temporal characteristic function $\chi (\eta )$ and the degree of second-order coherence $g^{(2)}(\tau )$ for a single-mode, degenerate parametric amplifier for a system in the Gaussian state, viz., a displaced-squeezed thermal state, to study the different criteria for nonclassicality. In particular, we contrast criteria that involve only one-time functions of the dynamical system, for instance, the quasiprobability distribution $P(\beta )$ of the Glauber-Sudarshan coherent or P-representation of the density of state and the Mandel $Q_M(\tau )$ parameter, versus the criteria associated with the two-time correlation function $g^{(2)}(\tau )$.

arXiv admin note: text overlap with arXiv:1610.08821