Lower- and higher-order nonclassical properties of photon added and subtracted displaced Fock states

TL;DR

This paper investigates the nonclassical properties of photon added and subtracted displaced Fock states, providing analytic expressions and comparing their nonclassical features, with implications for quantum optics applications.

Contribution

It offers new analytic expressions for nonclassicality witnesses and compares the effects of photon addition and subtraction on nonclassicality in displaced Fock states.

Findings

Photon addition enhances nonclassical properties more than subtraction.

States exhibit lower- and higher-order antibunching and sub-Poissonian statistics.

Proposed optical designs for generating these states from squeezed vacuum.

Abstract

Nonclassical properties of photon added and subtracted displaced Fock states have been studied using various witnesses of lower- and higher-order nonclassicality. Compact analytic expressions are obtained for the nonclassicality witnesses. Using those expressions, it is established that these states and the states that can be obtained as their limiting cases (except coherent states) are highly nonclassical as they show the existence of lower- and higher-order antibunching and sub-Poissonian photon statistics, in addition to the nonclassical features revealed through the Mandel $Q_M$ parameter, zeros of Q function, Klyshko's criterion, and Agarwal-Tara criterion. Further, some comparison between the nonclassicality of photon added and subtracted displaced Fock states have been performed using witnesses of nonclassicality. This has established that between the two types of non-Gaussianity inducing operations (i.e., photon addition and subtraction) used here, photon addition influences the nonclassical properties more strongly. Further, optical designs for the generation of photon added and subtracted displaced Fock states from squeezed vacuum state have also been proposed.