Research On The Preparation Of High Property Solid-State Dye Mediums And Tunable Laser Output Characteristics

Dye lasers have wide range of applications in many areas such as science, military, and medicine for their advantages including broad tunable range and high efficiency. Conventional liquid dye lasers cannot reach the comprehensive applications because their complicated liquid dyes solutions circulatory systems, toxic and flammable dyes and solvents, periodic replacing and cleanouting circulatory systems and conduits. Keeping the advantages of liquid dye lasers for various pumping styles and wide tunable range in the visible light waveband, solid-state dye lasers also have other advantages, such as all solid-state construction, little capacity, light weight, convenience for use and conservation, low cost and so on.Recently the research of solid-state dye lasers is mainly rest on low laser energy pump. The dissertation first systematically introduces and analyzes the development of solid-state dye mediums and tunable solid-state dye lasers. The dissertation studies the photodestruction mechanism of solid-host and photodegration of dye molecules, mass polymeric mechanism of MMA, and uses modified solid hosts method, doping modified method, modified solid hosts and doping modified together method, and dedicates to prepare modified solid-state dye mediums with high laser damage threshold, high laser efficiency, long lifetime (good photostability), and obtains solid-state dye laser output with wide tunable range, high dye laser energy.In order to enhance the lifetime, efficiency, damage threshold of solid-state dye mediums, the dissertation mainly chooses the methods with addition of low moleculer methanol, the methods with addition of low moleculer methanol and Coumarin dyes, the methods with addition of low moleculer methanol and other monomer, and prepares solid-state mediums doped with PM dyes and researches the impact of modification on their output characteristics. In the solid-state dye samples based on modified copolymers of MMA and HEMA with methanol doped with PM567, when the volume percent of doped methanol is 15%, the longest lifetime is 278 000 shots, and the corresponding normalized photostability is 180.7 GJ/mol, the photostability increased 8.7 times, the highest laser efficiency is 63.31%, and laser damage threshold is 6.7 J/cm2. In the solid-state dye samples based on modified PMMA with methanol co-doped with PM567 and C540A, the longest lifetime is 618 000 shots, the corresponding normalized photostability is 401.7 GJ/mol, and laser damage threshold reaches 7.9 J/cm2. Our results are the best are the present time. Solid-state dye samples doped with PM567, PM580, and PM597 are used as operating mediums under high pulse energy pump, the corresponding maxium dye laser output energy reach 432mJ, 412mJ, and 448mJ.Due to solid-state dye laser with narrow tunable range and low laser efficiency recently, depending on the basic theory of near-grazing-incidence grating, the dissertation designs tunable narrow linewidth laser oscillator cavity, and researchs tunable dye laser output characteristics of single-doped, co-doped and modified solid-state dye mediums. The photostability of tunable narrow linewidth solid-state dye lasers are also studied. When solid-state dye samples based on modified PMMA with methanol doped with PM567, PM580, PM597, PM650 are used as operating mediums, the narrow linewidth dye laser output with tunable ranges of 51.7nm, 52.1nm, 51.5nm, 63.9nm are obtained, and the corresponding laser efficiency are 42.59%, 42.7%, 37.62%, 9.39%. The tunable rrange is the best for the single-doped solid-state dye medium at the present time. Using solid-state dye sample doped with PM580 as operating medium, the broad and narrow band laser beam quality factor M2 are measured, and the beam quality factors are estimated to be Mx2=10.9 and 4.1 in horizontal direction and My2=10.7 and 3.9 in vertical direction for broadband and narrowband laser. The photostability of tunable narrow linewidth solid-state dye lasers under different pump energy density and different operating wavelength are first studied and the results show that the photostability are better when the samples operate at the emission wavelength with high conversion efficiency.Based on DFB solid-state dye laser with traditional refraction modulation, the dissertation introduces the dye into the liquid crystal and designs DFB structure for obtaining integrated tunable dye laser. The dye laser output characteristics are researched by theoretical and experimental methods. Tunable narrow linewidth dye laser output properties of PM567 doped nematic liquid crystal under holographic excitation are studied using theoretical and experiment methods, and tunable narrow linewidth dye laser output from 556 nm to 571 nm are obtained. The results are very important for future research on tunable dye laser output with dye doped LC under applied electric field and its practical application.In order to obtain tunable narrow linewidth solid-state dye laser and ultraviolet laser output with high pulse energy and wide tunable range, the dissertation designs tunable narrow linewidth solid-state dye laser oscillator-amplifier and amplifier-doubling frequency configuration, and researches solid-state dye laser amplified output characteristics and doubling frequency output characteristics. Using solid-state dye samples doped with PM567, PM580, and PM597 as amplified operating mediums, narrow linewidth solid-state dye laser output with tunable range 48nm, 48nm, 58nm are obtained, and the highest slope efficiency of 51.39% at 560nm, 50.62% at 560nm, 36.25% at 590nm are obtained, and the corresponding maximum output energy are 113.9mJ, 116.2mJ, 114.1mJ. Using BBO crystal to frequency double the dye laser into ultraviolet and solid-state dye sample doped with PM597 as operating medium, ultraviolet dye laser output are demonstrated with a continuous tunable range from 279 to 305 nm, and the highest UV laser output energy reaches 6.94mJ. The experiment results show that the use of solid-state dye laser samples as operating medium, tunable narrow linewidth solid-state dye laser and ultraviolet laser output with a single high pulse energy can be obtained, and reach practical level.