Miniature All-Sapphire Single-Crystal Fiber Fabry-Perot Sensor Fabricated by Femtosecond Laser Micro-machining and CO2 Laser Welding

This paper reports a miniature all-sapphire high temperature fiber sensor based on fiber Fabry-Perot interferometer fabricated by femtosecond laser micromachining and CO 2 laser welding. The sensor was tested to 1455°C with up to 5.38 nm/°C sensitivity.