| Laser physics is an important part of quantum optics.The presence of the laser has a significant impact on the quantum optics,it played an important role for its development.Mollow predict the dressed-state laser,it was proved by the later experi-ments.The properties of laser like the intensity of lasers,laser linewidth and fluctuation are what we interested on.In this paper,we study the model two-level atom coupled to a single cavity mod-e,and driven by a strong external field. while the frequency of external field is large,and the frequency of cavity tuned to Mollowsideband,lasers occur.We use the langevin ap-proach,give the exact solution of the intensity of laser when the system is in steady state,and obtained the expression of laser linewidth and Mandel parameter Q. We plot figures,and then analyse these figures,we get the law of these properties and some reasons of that.We discuss the effect of the spontaneous emission rate γ and coupling constant g to laser intensity, linewidth and Mandel parameter Q.We obtain that:while δ>0,the same as ω>ωL,no laser occur.but when δ<0the intensity was large,lasers occur. The amplification coefficient of the dressed-laser is proportional to a product of the pumping rate and coupling constant g1。While δ<<0or δ≈0,the value of Q is very large;whlie the value of δ made the intensity large,the value of Q would be small and even tend to zero.When we change the value of δ so that the intensity is large,the linewidth would be small,like the Mandel Q,made monochromaticity of laser strong. |
