  In the present work the model of a single-atom laser generating in the regime
when incoherent pumping rate coincides with the cavity decay rate is
theoretically investigated. Using the stationary equation for the phase
averaged Glauber P function the analytical expressions for mean number of
photons and its dispersion are obtained. In the limiting case of the
strong-coupling regime the exact expression for the photon number distribution
function is found. Obtained results describe the sub-Poissonian photon
statistics and show an increase in mean number of photons to non-zero value
when the pump tends to zero.
