A Rubidium Vapor Laser End-pumped By A Tunable Laser With A Narrow Linewidth

An optically pumped alkali vapor laser is based on the saturated vapor of alkali as the laser gain medium.Compared with other conventional high-power lasers,it has its own outstanding advantages and performance.The alkali vapor laser with advantages of solid-state lasers and gas lasers has a high quantum efficiency.The wavelengths of alkali vapor lasers are close to atmospheric transmission windows.Because the laser gain medium is gas,it is easy to flow and reduce heat.The alkali vapor laser with a great potential for a high power,has good applications in the military,aerospace,laser processing,basic physics and medical fields.Many researchers pay attention to alkali vapor lasers,which have become a new research direction and hotspot in the field of laser research.In this thesis,the theory and experiments of optically end-pumped rubidium vapor laser by a tunable laser with a narrow linewidth have been studied.Firstly,optical properties for rubidium atoms,solutions to the problems of alkali vapor lasers,and interactions with buffer gases are analyzed.The three energy level laser rate equations based on model for optically end-pumped rubidium vapor laser are proposed.The performances of rubidium vapor laser containing hydrocarbons and no hydrocarbon molecules are simulated,which are influenced by the buffer gas and temperature on the gain medium.These simulations provide theoretical guidance for the experiment of an optically end-pumped rubidium vapor laser.Meanwhile,basic principle of an excimer laser(XPAL)and the corresponding operation mode are briefly described.The four energy level laser rate equations of alkali-rare-gas excimer laser are established.The effects of buffer gas,length of gain medium,and operating temperature on the output performances of Rb-Ar and Rb-Kr excimer lasers are analyzed.These analyses provide theoretical guidance for the experiment of an optically end-pumped Rb-Ar excimer laser.To efficiently pump the alkali laser system,a tunable Ti: sapphire laser system with a narrow linewidth and a high power is established,which is operating at room temperature.The Ti: sapphire laser is pumped by 532 nm laser.In order to tune the laser wavelength and compression the width,a prism and a birefringent filter are laid in the laser cavity.The output laser of the Ti: sapphire laser is in accordance with the pumping source for Rb vapor laser.The pumping laser for Rb-Ar excimer laser can also be obtained by tuning the prism and the birefringent filter simultaneously.An optically end-pumped alkali Rb vapor laser is studied.An alkali vapor cell has been designed independently,which can replace the laser gain medium and fill the buffer gas repeatedly.The buffer gas circulation system is built,and an optically end-pumped alkali vapor laser system is established.In experiments,the narrow-linewidth Ti: sapphire laser with a center wavelength of 780 nm is utilized as pump source for Rb-He-methane gain medium.The rubidium laser with a wavelength of 795 nm is obtained.The main reasons for the low efficiency of the Rb laser are analyzed,and the methods to solve the problem are proposed.The experimental research on the improved laser system is also carried out.Lastly,an optically end-pumped Rb-Ar excimer laser is investigated.The Rb-Ar gas mixture is filled into the self-designed vapor cell.A Rb-Ar excimer laser with a wavelength of 780 nm is realized,which is pumped by the Ti: sapphire laser with a center wavelength of 755 nm.Not only is the absorption width of Rb-Ar excimer measured,but also the property of broadband pumping for Rb-Ar excimer laser is verified,when the pump wavelength varies from 754 nm to 759 nm.Finally,the main reasons for the low efficiency of Rb-Ar excimer laser are listed,and corresponding solutions are introduced.