High-sensitivity photonic crystal diaphragm based sapphire Fabry-Perot acoustic sensor for high-temperature applications

This paper presents a sapphire based fiber optic Fabry-Perot (F-P) acoustic sensor with photonic crystal (PC) diaphragm for high-temperature applications. The sapphire based PC diaphragm has been designed through rigors theoretical analysis while its performance is verified by numerical simulations. The sensor is also characterized theoretically via lumped paraments model and F-P interference model, the result shows excellent dynamic property and sensitivity, especially at least two orders of magnitude in sensitivity enhancement compared with normal sapphire F-P sensor, which shows excellent availability in acoustic sensing. Meanwhile, the high temperature-resistance of PC diaphragm also shows broad prospect in high-temperature applications.