Solid State Radially Polarized Picosecond Laser Technology Research

Ultra-short laser pulse has the characteristics of high peak power, wide spectrum,high repetition frequency etc. It has been widely used in communication, laserprocessing, medicine, biology, physics, and many other fields. The currently usingultra-short laser pulse is mainly natural polarization and linear polarization. Theresearch of radially polarized ultra-short laser is very few. In this paper, the generationof radially polarized mode-locked laser with LD side-pumped Nd:YAG is studied.Introduce the domestic and foreign development of radially polarized laser, thecharacteristic and advantage of radially polarized laser in application, the theory ofgenerating radially polarized laser and the development of mode-locked radiallypolarized laser. Introduce the characteristic of SESAM, the ultimate principle ofSESAM mode-locked laser, the development of SESAM mode-locked laser, thepresent development of SESAM mode-locked laser with side-pumped Nd:YAG andthe effects on mode-locked with different SESAM parameters.Side-pumped mode-locked radially polarized laser is analyzed, designed andexperimental studied. Including the following sections:1. Analyzing the thermal effects of Nd:YAG, measuring thermal focal length withdifferent method and compared the results.2. Analyzing the design of resonators and the selection of SESAMs. Realize theoutput of continuous wave mode-locked radially polarized laser; the output power is13W; the pulse width is122ps.3. Measuring the purity of the radially polarized beam, the purity is above92%.The effects of travelling-wave amplifier and the thermal depolarization on the radiallypolarized laser are studied.4. Analyzing the problems and main influence existing in the experiment. Make asimple summary and prospect of the experiment.