Ld End-pumped Nd: The Gdvo <sub> 4 </ Sub> Thermal Effect Study

Laser-diode (LD) pumped solid-state lasers have the advantages of full solid state, small volume, high pump efficiency, etc. They can be widely used in many fields such as communication, industry and military. End-pumping is an efficient way to get high output power for solid-state lasers. However, with high pump power, part of the input energy is unavoidably converted into thermal energy inside the laser media, which leads to the non-uniform temperature distribution and thus results in the non-uniform change of refractive index of the laser media, thermal-caused birefringence, thermal stress and strain as well as end-face distortion. These thermal effects greatly influence the performance of lasers, especially in end-pumped solid-state lasers. With the development of laser technology in the recent decades, thermal effects of laser media have become one of the most important factors that should be considered in laser designation and optimization. It is very necessary to study the thermal effects of laser media in LD end-pumped solid-state lasers.As a new host material for Nd³⁺ ion, the GdVO₄ crystal has a higher absorption cross section at 808nm, a larger emission cross section at 1.06 μm and a larger thermal conductivity compared with the typical LD solid-state laser media Nd:YAG and Nd:YVO₄. A lot of research has been done on the performance properties of Nd:GdVO₄ lasers. However, as far as we know, there is no report on the thermal focal length of Nd:GdVO₄ crystal. So it is very important to study the thermal effect of Nd:GdVO₄.In this thesis, according to the basic ways of studying the thermal effect in laser media, a novel but more efficient method was promoted to determine the thermal focal length of laser media in resonator cavity. By this method, the thermal focal length of Nd:GdVO₄ crystal was determined. The main content includes:...