Study On The Technology Of Ho:YAG Ceramic Continuous Acoustic-optic Mode-locking And Its Stability

2μm laser can be used for the photon medicine, remote sensing, metrological and as a pump source for the nonlinear frequency conversion because of it is in the band of eye safe and atmospheric window. Mode-locked laser have the advantage of narrow pulse width, high peak power, high repetition rate and therefore have the extensive application in the fields of spectral technology, material processing, medical operation, underwater exploration, chemical reaction and molecular dynamics. Moreover, because of the low cost, easy processing and high doping concentrations, the ceramic has high application value. The purpose of this thesis is to use appropriate locking technology to get stable, picosecond pulse based on ceramic, and make it more practical.Firstly, we analyzed the parameters of the particle number inversion ratio of the laser according to the Ho:YAG rate equation, and the gain curve of Ho:YAG is calculated according to the absorption spectra and emission spectra of Ho:YAG ceramic. At the same time, we analyzed and discussed the principle of the active mode locking, and calculate the pulse width with the gain curve. The etalon effects response to the widening of the pulse width was analyzed, and the power relationship between the lock mode and the free oscillating was analyzed.Then the acousto-optic mode-locked pumped by Tm:YLF laser is preliminary studied, as the result is not ideal, so we analyze the effect of relaxation oscillation on the mode-locked laser. We propose the improvement project by analyzed the spot, feedback and pump source et al. The laser pumped by the Tm:YLF is improved by using the project, and the mode-locked laser can be stabilized at a few minutes.Finally, we get the Ho:YAG ceramic laser and Ho:YAG crystal laser pumped by Tm fiber laser which can be stabilized for over two hours. We analyzed the characteristics of the power, pulse width, spectrum and the beam quality. The pulse width is 241ps(Ho:YAG ceramic) and 294ps(Ho:YAG crystal), the repetition rate is 82.15 MHz and 81.92 MHz, the maximum power is 1.84 W and 3.41 W respectively and the beam quality is 1.16.