Quantum states in a one atom maser

The one atom maser is an archetype experiment of quantum optics, where the interaction is between the basic quantum components of a single atom and a single mode field, uncluttered by unwanted side effects. Thus the one atom maser is able to examine the most fundamental aspects of the atom light interaction. In this paper we review three of the most recent experiments on the very topical subject of photon Fock state creation. Namely the creation Fock states via trapping states, dynamical Fock state preparation using state reduction of lower state atoms arid finally the creation of Fock states on demand. In the two decades since its first operation, the one atom maser continues to operate at the forefront of quantum optics research having produced many first class results. We present some taste of future, as we turn the micromaser to quantum computing and the creation of exotic entangled states