Study On High-peak Power Yb-doped Pulsed Fiber Laser

In this thesis, ytterbium- doped double- clad fiber laser has been presented theoretically and experimentally which is based on the radiation rate equation of four-level ytterbium ion, and explained the working principle and key technology of ytterbium- doped double- clad fiber laser. In theory, we have obtained the influence of doping concentration, the fiber length, fiber radius, reflectivity of the output mirror and pumping power on the output characteristics of laser. And based on the simulated result we optimize the design of the final model in order to realize the peak power of the laser output. Then, we build the acousto-optic Q-switched pulse fiber laser by using the experimental method, which output high – energy laser pulses through the level of ytterbium doped fiber amplifier and the repetition frequency of the laser can be adjustable. We measured the relationship between laser pulse width and modulator rise time, and analyzed the influence of modulation signal duty ratio on the output pulse waveform.