Abstract We present a study on the quantum statistical properties of radiation in a onephoton micromaser. In particular, the possibility of generating steadystate squeezing is investigated. The spectral properties of the radiation field in a micromaser are also studied. We show that the steadystate squeezing can be generated in a lossless micromaser by injecting the atoms in a coherent superposition of upper and lower states. It is shown by considering initial vacuum number and thermal state of the cavity field, that for a particular choice of the interaction time field evolves to a squeezed state. Steady state squeezing is found to be independent of the initial state of the cavity field. However, the temporal evolution of the squeezing depends on the initial state of the field. Effects of cavity losses and pump fluctuations on steadystate squeezing are also investigated. Finally, an exact analytic expression for the linewidth of a micromaser in the absence of cavity losses is obtained by evaluating the twotime correlation function. A comparison with the natural linewidth of laser shows that under certain conditions gain contribution to the linewidth is same in both the cases. We also, derive an exact expression for the phoston distribution function and show that for a particular choice of the interaction time, the number state of the field can be generated.
