Abstract We present a laser-assisted preparation of transparent europium-titanate Eu2Ti2O7 thin films with tailored structural and optical properties. We have evaluated the effects of the irradiation time on the structural and the optical properties of the films. This approach allows the preparation of nanocrystalline crack-free films and micro patterns. The amorphous thin films were prepared by a sol-gel method. The films were annealed by a CO2 laser beam for various time intervals. The laser irradiation induced a crystallization process that resulted in the formation of Eu2Ti2O7 nanocrystals. The nanocrystals regularly grew with increasing irradiation time reaching the size from 25 nm to 45 nm. A film of a thickness 480 nm exhibited an optical transmission of 91.9% that is close to the maximal theoretical limit. The film's refractive index at 632 nm was 2.26. A micrometric pattern was prepared by a direct laser writing followed by a wet chemical etching. Feasibility of the demonstrated approach, together with the high film's quality, and europium-titanate chemical resistivity open up many opportunities for advanced applications. The approach can be used for a preparation of protective coatings and integrated photonic devices such as planar optical waveguides and couplers.

中文翻译：

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CO 2 激光辅助制备透明Eu 2 Ti 2 O 7 薄膜

摘要 我们提出了一种具有定制结构和光学特性的透明铕钛酸 Eu2Ti2O7 薄膜的激光辅助制备方法。我们已经评估了照射时间对薄膜结构和光学性能的影响。这种方法允许制备纳米晶无裂纹薄膜和微图案。采用溶胶-凝胶法制备非晶薄膜。薄膜通过 CO2 激光束退火不同的时间间隔。激光照射引起结晶过程，导致形成 Eu2Ti2O7 纳米晶体。纳米晶体随着照射时间的增加有规律地生长，尺寸从 25 nm 增加到 45 nm。厚度为 480 nm 的薄膜表现出 91.9% 的光透射率，接近最大理论极限。电影' 632 nm 处的 s 折射率为 2.26。通过直接激光写入和湿化学蚀刻制备测微图案。演示方法的可行性，加上薄膜的高品质和钛酸铕化学电阻为高级应用开辟了许多机会。该方法可用于制备保护涂层和集成光子器件，例如平面光波导和耦合器。