The article has analysized the mechanism of the pump power hysteresis and wavelength tuning theoretically and experimentally, and validate the analysis result of the pump power hysteresis in simulation.

Pump power hysteresis effect is investigated in a fiber laser based on nonlinear polarization rotating technique.

The influence of the pump power to passive Q-switched period of Nd:YVO4/Cr4+:YAGLaser have been analysed by Theoretical and studied by experimental, then draw a conclusion : the power density is Increasing and the period of Q-switched pulse is becoming short and the account of Q-switched pulse in a pump square wave is increasing following the increase of pump powe

On the basis of the rate equation model of the 3-energy-level-system fiber lasers,this paper focuses on the effects of the reflection coefficient of the input mirror R1,the reflection coefficient of the output mirror R2 and the pump power on the optimum length of the cladding fiber lasers L with a numerical emulator,producing a significant result for the study on cladding-pumped fiber lasers.

Also the relation between the erbiumdoped fiber′s length, pump power, input signal intensity and gain, ASEN of EDFA is given.

For annealed proton exchange Nd∶MgO∶LiNbO 3 waveguide lasers,by assuming Gaussian/Hermite Gaussian and Gaussian/two half Gaussian mode intensity distributions in the direction of width/depth of the waveguide,the threshold pump power and slope efficiencies were calculated and compared with experimental results.

Starting with rate equation and taking the spatial distributions of pump and laser modes into account,we have derived the general expressions of the threshold pump power and slope efficiency for Nd:MgO:LiNbO 3 and Ti diffused Er:LiNbO 3 waveguide lasers.