Optical Transmission Bistability Of 2?m Single Mode Laser In Tm Doped Media With External Resonator Feedback

Optical bistability is a very important research direction among nonlinear optics and its application value in the future also attracts more and more attention.Realizing the light path in space communication technology,optical bistability can be used to implement trigger,optical switch,optical logic,light cache,optical computing and optical coding,etc.On the other hand 2 um laser is in the atmospheric transmission window,and the human safety light band which is also applied to atmospheric optical transmission and the best light source for atmospheric optic.In this paper,we use the methods of rate equation and get the solution for the two-level particle number density of thulium doped crystal and nonlinear absorption and refraction expression under 2 um signal light effect.Then selecting Fabry-Perot cavity to provide feedback to optical bistability,using the method of multiple beam interference is deduced considering the cavity in the absorption loss of Fabry-Perot cavity spectral response,and by the nonlinear absorption of thulium doped crystal refractive index and the fusion,external cavity feedback to thulium doped crystal optical bistability physical model.After getting equation,first of all,give the typical optical bistability curve by means of the optical bistability behavior.Then analyze the optical bistability curve by changing the physical parameters.Finally,on the basis of optical bistability numerical solution,through the appropriate physical approximation and assumed that,by means of complete parsing directly parse analyze solution and the physical existence conditions for solving equations,description and characterization of transmission characteristics of bistable parameter is given.On the analyze relationship between the physical parameters,discussed clearly a bistable mechanism and regulation scheme.