Recent advances on fabricating in-fiber gratings in single-crystal sapphire fiber

Abstract

In this paper, a brief review of recent advances on fabricating in-fiber gratings in single crystal sapphire fiber is presented, which includes (1) backgound on fiber gratings, (2) in-fiber grating fabrication methods in single crystal sapphire fiber, (3) the variation of spectral response of sapphire fiber grating induced by the change of ambient refractive index, and (4) reflection-type fiber specklegram generated in single crystal sapphire fiber. The application of this unique fiber grating to harsh environment, high temperature, distributed fiber optic sensor will also be discussed.