Abstract
The photon statistical properties of a bistable system consisting of a saturable m-photon absorber (m = 1, 2, ) inside a resonator which is externally pumped by a laser beam have been theoretically investigated. With the help of an approximation scheme valid for n ¥ 1, jn 2 n 2 (where n; is the mean value and jn 2 the variance of the photon number), an analytical expression is derived for the quantity j n2/n. It turns out that in the bistable region two different values of jn 2/n are possible for a given value of the input field amplitude.