Antibunching: more than one kind in two-photon absorption

Abstract

Properties of the second moment of the photon distribution and intensity autocorrelation function are examined in a system undergoing only two-photon transitions. These properties are interpreted in terms of two kinds of antibunching, strict and temporal. It is shown that antibunching is a richer class of phenomena than usually supposed and that temporal antibunching may be easier to observe than the strict antibunching usually considered.