Sapphire fiber has been widely utilized in ultra-high-temperature environments.A sapphire fiber Bragg grating(SFBG)is a potential high-temperature sensor,but the multimodal behavior results in a broadband reflection s...Sapphire fiber has been widely utilized in ultra-high-temperature environments.A sapphire fiber Bragg grating(SFBG)is a potential high-temperature sensor,but the multimodal behavior results in a broadband reflection spectrum and poor precision.In this article,we report a helical tapered depressed cladding waveguide(HTDCW)by using a femtosecond laser direct writing technique to realize single-mode operation of SFBG.The HTDCW was created using helical negative refractive index modification by forming a depressed cladding.展开更多
基金National Key Research and Development Program of China(2023YFB3208600)National Natural Science Foundation of China(62222510,62435012,62375176,T2421003)+1 种基金Guangdong Provincial Department of Science and Technology(2024A1515010108)Ling Chuang Research Project of China National Nuclear Corporation(CNNC-LCKY-2024-067)。
文摘Sapphire fiber has been widely utilized in ultra-high-temperature environments.A sapphire fiber Bragg grating(SFBG)is a potential high-temperature sensor,but the multimodal behavior results in a broadband reflection spectrum and poor precision.In this article,we report a helical tapered depressed cladding waveguide(HTDCW)by using a femtosecond laser direct writing technique to realize single-mode operation of SFBG.The HTDCW was created using helical negative refractive index modification by forming a depressed cladding.
