Quantum-fluctuation properties of the ladder scheme of a three-level laser with incoherent pumping

The dynamics and quantum statistical properties of the three-level laser ladder model are investigated. A comparison between this model to the other models, V and Λ ones, is presented. We found that the ladder-pumped lasers have both the highest intensity and the lowest linewidth, whereas the maximum noise reduction is more pronounced in the V and Λ models. We also show that at high pumping rate the ladder scheme behaves as the two-level one.