Theoretical study of higher order nonclassicality in intermediate states

Abstract

A state of radiation field which cannot be described by a non-negative and well defined Glauber Sudarshan P-function is called nonclassical state. Squeezed state and antibunched state, which have been extensively studied in the last few decades, are examples of lowest order nonclassical state. Higher order nonclassicalities (e.g. higher order antibunching (HOA), higher order subpoissonian photon statistics (HOSPS), higher order squeezing (HOS)) are not yet studied rigorously. Diferent kind of higher order nonclassical phenomena are studied in the present thesis. The study is mainly focused on a particular class of quantum states which are known as intermediate states. Mutual relationship between different criteria of higher order nonclassicality is also studied. In that study it is found that the HOA, HOSPS and HOS are independent phenomenon. Since the introduction of binomial state as an intermediate state, diferent intermediate states have been proposed in the literature. Different nonclassical effects have also been reported in these intermediate states but most of these reports are limited to lower order nonclassicality. Before the present study, higher order antibunching was predicted in only one type of intermediate state, which is known as shadowed negative binomial state.