Multiatom and transit-time effects on photon-correlation measurements in resonance fluorescence

Abstract

An expression is derived for the expected number of photon pairs separated by a time interval $\ensuremath{\tau}$ that are detected in photoelectric correlation measurements of an atomic beam, when due account is taken of the fluctuations of the number of radiating atoms and of the effect of their finite transit time through the field of view. The theoretical expression is checked against some recent measurements and good agreement is obtained.