Tapping states: Effect of pump phase fluctuations in micromaser

We presented the exact solution for the photon statistics of one-mode $\Lambda -$type micromaser, including the effect of finite natural linewidth of microwave pump field. It is shown that trapping states exist in a $\Lambda -$type micromaser even for finite temperature limit and finite value of natural linewidth of the microwave pump field. A periodic dependence on interaction times is shown to arise as we move from zero to finite linewidth values.