Self-organized microgratings in LiNbO3 fabricated by a slit-shaped femtosecond laser for optical attenuation. (May 2023)

• Record Type: Journal Article
• Authors: Zhou, Sikun; Wang, Shutong; Gu, Baoshan; Shen, Li; Huang, Fei; Wang, Sha; Deng, Guoliang; Zhou, Shouhuan
• Is Part Of: Optics & laser technology. Volume 160(2023)
• Publication Date: 2023-05
• Subjects: Self-organized microgratings -- Femtosecond laser -- LiNbO3 -- Attenuator; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2022.109066
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: The method of preparing self-organized micro-gratings is slit shaped femtosecond laser directing writing. The method of preparing self-organized micro-gratings can produce uniform self-organized micro-gratings with a period of 1.57 μm to 2.68 μm. The maximum attenuation ratio of this self-organized micro-gratings based attenuator is about 45.7 % to 633 nm. Abstract: Preparing multifunctional 3D microstructures in transparent materials, such as phase plates, light attenuators, and metasurfaces, is critical in science and technology. Here, the self-organized micro-gratings were created inside the z-cut LiNbO3 using slit-shaped femtosecond laser direct writing. The effects of the processing parameters and slit widths on the micro-grating's formation are investigated. The Raman mapping, energy dispersive spectroscopy, and the micro polariscope are adopted to understand the general mechanism of periodic gratings' generation. An optical attenuator with a spacing of 15 μm was fabricated to demonstrate the potential of micro-grating. The attenuator showed the max attenuation (about 45 %) at 633 nm, indicating the potential application of micro-gratings in optical information processing. The micro-gratings provide a pathway for expanding the applications of LiNbO3 and fabricating multifunctional photonic structures.