sentences:  From these two functions it is easy to see that in the weak field limit a single peak appears at formula_70 in the spectral density due to the delta function, while in the strong field limit a Mollow triplet forms with sideband peaks at formula_71, and appropriate peak width of formula_43 for the central peak and formula_44 for the sideband peaks.Photon anti-bunching is the process in Resonance Fluorescence through which rate at which photons are emitted by a two-level atom is limited.A two-level atom is only capable of absorbing a photon from the driving electromagnetic field after a certain period of time has passed.