以正硅酸乙酯为原料,采用溶胶-凝胶法制备SiO₂溶胶,通过提拉法涂制多孔SiO₂减反膜,并在多孔SiO₂减反膜上涂制一层甲基三乙氧基硅烷(MTES)预聚体。通过疏水的MTES预聚体涂制在多孔SiO₂减反膜上,对多孔SiO₂减反膜的表面进行改性,以提高膜层的环境稳定性。经过表面改性的复合膜层的透过率峰值可达99.67%,折射率为1.231,水接触角达123.6°,在相对湿度为95%的环境中放置475 d后膜层的峰值透过率为99.09%,稳定性提高明显。膜层表面平整,激光损伤阈值约为24.5 J/cm ²。

以钛酸正丁酯、正硅酸乙酯为前驱体,在薄膜设计软件的辅助下,采用溶胶-凝胶法在K9光学玻璃上制备了λ/4-λ/2-λ/2膜系宽带减反膜。该膜层的光学性能良好,在500~900 nm波长范围内的平均透过率为99.25%,透过率增益随入射角增加而增大,斜入射光入射角从0°增至60°仍能有效覆盖钕玻璃的主吸收峰,此时平均透过率增益从7.2%增至10.2%;在150 ℃下进行热处理后,膜层具有一定的耐擦拭性能,表面均匀性良好,均方根粗糙度为4.00 nm。

神光Ⅱ大型固体高功率激光装置是我国激光驱动器发展历史的里程碑, 其成功研制使我国高功率固体激光工程与技术、聚变物理与基础物理研究实现了全面且本质的跨越式发展。简要概述了神光Ⅱ激光装置研制中创新发展的大量工程方案与技术手段, 举例介绍了神光Ⅱ激光装置在近20年来的高质量运行中取得的众多有国际影响力的研究成果。经多方支持和多年持续发展, 已经形成数万焦耳级纳秒激光装置、皮秒拍瓦以及飞秒拍瓦激光装置等, 这些装置是我国惯性约束核聚变、强场物理、高能量密度物理等研究领域中重要的物理实验核心平台之一。

The silica suspension was prepared by a sol gel method using tetraethylorthosilicate (TEOS) as precursor and ethanol as solvent. The stability of the sol system was observed by particle size test. The particle size maintained at about 6.5 nm for 4 months. The quartz substrates were coated by a dipping method and heat treated at 200 ℃ and 800 ℃ in a muffle burner. The film transmittance curve moves to short wavelength direction by about 210 nm, and both the transmittance peaks are more than 99.8%. Therefore, the film’ optical properties are excellent. The stabilities of film heat treated at different temperatures were researched in different humidity environments. The transmittances of the films heat treated at 200 ℃ are more than 99.9% and the wavelength of film transmittance peak decreases by about 150 nm. The transmittances of the films heat treated at 800 ℃ reduces by 0.3% and the wavelength of film transmittance peak maintain at 600 nm.

Antireflective coatings prepared by sol gel method are importantly used in high power laser devices, the stability of colloidal, laser induced damage thresholds (LIDTs) and antireflective efficiencies of coatings resulted from different particle sizes silica colloidal suspensions and silica antireflective coatings are studied by controlling different molar ratios of water and tetraethoxysilane (TEOS). The results show that the transmittance of porous silica antireflective films is higher than 99.5% and LIDTs are greater than 62 J/cm2 (1064 nm, 15 ns), the transmittance and LIDTs of smaller particle size silica antireflective film reaches 99.75% and 77.42 J/cm2 (1064 nm, 15 ns), respectively. The average particle sizes of colloidal suspensions increase with the mol ratio of H2OTEOS, the particle size quickly increases when the molar ratio of water and ester is greater than 3.5. The solution with particle size below 10 nm has excellent stability, and the particle size and viscosity of the solution is almost not unchanged. The stability of films with different particle sizes in different humidities is researched, all the films′ transmittance in high humidity drops and the film with larger particle size has more obvious decrease in transmittance, and therefore the chemical films are more suitable for the use in low humidity environment.

溶胶凝胶法制备减反膜在高功率激光装置中有着重要运用，通过控制水与正硅酸乙酯(TEOS)不同特质的量之比制备不同粒径大小的二氧化硅悬胶体及二氧化硅减反膜，可以研究悬胶体粒径大小对溶液及膜层的激光破坏阈值、光学减反效率稳定性影响。结果表明制备获得的多孔性SiO2减反膜透射率均高于99.5%，激光破坏阈值均大于62 J/cm2(1064 nm,15 ns)，其中粒径小的SiO2减反膜透射率达到99.75%，激光破坏阈值高达77.42 J/cm2(1064 nm,15 ns)。随着水酯物质的量比值增大，悬胶体溶液平均粒径增大，当水酯物质的量比值大于3.5时粒径增大幅度加快；粒径在10 nm以下的溶液具有优异的稳定性，溶液颗粒大小、粘度等性能基本保持不变。在不同湿度环境下研究不同粒径膜层的稳定性，所有膜层在高湿度环境中透射率有所下降，其中大粒径膜层下降更明显，化学膜更适合在湿度低的环境下使用。

在SiO2溶胶合成阶段进行化学改性，将六甲基二硅氮烷（HMDS）引入SiO2溶胶，制得稳定的胶体,胶体中SiO2纳米颗粒表面的亲水性Si-OH基团被疏水性的Si-O-Si(CH3)3基团取代。采用旋转法在磷酸二氢钾(KDP)晶体表面涂膜，涂膜晶体峰值透射率99%以上。膜层光学均匀性良好，表面粗糙度均方根值为0.94 nm。膜层疏水性能好，水接触角达到140°。涂制疏水性SiO2基减反膜的KDP晶体无需热处理就具有较好的疏水防潮性能，与目前激光器使用的防潮减反双层膜相比，在室温高湿度条件下涂膜晶体透射率下降情况大致相当。旋转涂膜可以有效解决三倍频晶体入光面与出光面共3个波段需减反的问题。

In order to improve the laser-induced damage threshold (LIDT) of the ZrO₂ film, the effect of polyvinyl pyrrolidone (PVP) with different average molecular weight on coatings is studied. The ZrO₂ sol is prepared by the hydrolysis of zirconium n-propoxide with acetylacetone as the chelating agent. The PVP (K16-18) is more suitable to obtain high LIDT coatings than other PVPs. The LIDT of the ZrO₂-PVP coatings is improved with the increase of the PVP (K16-18) content. When the PVP (K16-18) content is 2.4 wt.-%, the LIDT of the ZrO₂-PVP coatings is 43.5 J/cm² (1064 nm, 12 ns). The ZrO₂ sol and ZrO₂-PVP (K16-18) sol have the good stability in 3 months. The refractive indices of the ZrO₂-PVP coatings decrease with the increase of the PVP (K16-18) content.

以锆酸丙酯[Zr(OPr)4]、正硅酸乙酯(TEOS)为原料, 用溶胶-凝胶(sol-gel)提拉法涂膜, 制备高透过的λ/ 4～λ/ 4型ZrO2/SiO2双层减反膜。该减反膜的表面均匀, 均方根(RMS)粗糙度为1.038 nm, 平均粗糙度(RA)为0.812 nm。制备的双层减反膜具有很好的减反效果, 在石英玻璃基片二面涂膜, 在激光三倍频波长351 nm处透射比达到99.41％, 比未涂膜石英玻璃基片的透射比提高了6.14％;在基频波长1053 nm处透射比达到99.63％, 比未涂膜K9光学玻璃基片的透射比提高了7.67％。膜层具有较高的激光损伤阈值, 在激光波长为1053 nm, 脉冲宽度为1 ns时, 薄膜的激光损伤阈值达到16.8 J/cm2。膜层具有良好的耐擦除性能。