2024/11/17 by Riku Imamura, Shun Fujii, Imamura, Riku +5
Engineering · Physics and Astronomy · #FOS: Physical sciences #Optics (physics.optics) #Photonic Crystals and Applications #Photonic and Optical Devices #Semiconductor Lasers and Optical Devices
paper · pdf · doi:10.48550/arxiv.2411.11018
openalex publication_date 2024/11/17 · openalex created_date 2024/11/21 · openalex updated_date 2026/07/28
This study explores sol-gel methods for fabricating erbium-doped silica microtoroid resonators, addressing the limitations of conventional doping techniques and enhancing device scalability. We develop a reproducible sol-gel process that yields defect-free films for photonic applications, and detail common defects and troubleshooting strategies. Two fabrication methods are compared: traditional film deposition on substrates and the direct coating of prefabricated resonators. The latter enables the fabrication of larger resonator diameters (up to 450 μm) without buckling, while achieving a high-Q factor and a low lasing threshold of 350 μW. These erbium-doped resonators exhibit multi-mode laser oscillations at 1550 nm, revealing the sol-gel method's potential for realizing scalable, gain-doped photonic devices.