Al₂O₃ coating is chemically unstable in hot water and transforms into a porous structure with a broadband anti-reflection (AR) property. We investigate the influences of treatment time on the AR property and structure morphology of the Al₂O₃ coating deposited by electron beam evaporation. Al₂O₃ coating treated for 7 minutes is found to possess the best AR property with an average reflectance of approximately 0.3% in the wavelength range of 350 nm to 1100 nm. The genetic algorithm simulation shows the treated Al₂O₃ coating possesses a graded-refractive index profile. The scattering calculation shows a large scattering in the short wavelength range. Moreover, we investigate the laser-resistance of the treated Al₂O₃ coating, and it shows the potential for application in laser systems.

中文翻译：

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具有梯度折射率分布的Al ₂ O ₃减反射涂层，用于激光应用

Al ₂ O ₃涂层在热水中化学不稳定，并转变为具有宽带减反射（AR）特性的多孔结构。我们研究了处理时间对电子束蒸发沉积的Al ₂ O ₃涂层的AR性能和结构形态的影响。发现处理7分钟的Al ₂ O ₃涂层具有最佳的AR性能，在350nm至1100nm的波长范围内具有约0.3％的平均反射率。遗传算法仿真显示处理后的Al ₂ O ₃涂层具有渐变折射率分布。散射计算显示出在短波长范围内的大散射。此外，我们研究了经过处理的Al ₂ O ₃涂层的耐激光性能，它显示了在激光系统中应用的潜力。