title: Optic sensors of high refractive-index responsivity and low thermal cross sensitivity that use fiber Bragg gratings of >80 degrees tilted structures.
abstract: For the first time to the authors' knowledge, fiber Bragg gratings (FBGs) with >80 degrees tilted structures have been fabricated and characterized. Their performance in sensing temperature, strain, and the surrounding medium's refractive index was investigated. In comparison with normal FBGs and long-period gratings (LPGs), >80 degrees tilted FBGs exhibit significantly higher refractive-index responsivity and lower thermal cross sensitivity. When the grating sensor was used to detect changes in refractive index, a responsivity as high as 340 nm/refractive-index unit near an index of 1.33 was demonstrated, which is three times higher than that of conventional LPGs.
authors.affiliation: Photonic Research Group, Aston University, Birmingham, UK. k.zhou@osa.org
authors.forename: Kaiming
authors.initials: K
authors.lastname: Zhou
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Chen
authors.forename: Ian
authors.initials: I
authors.lastname: Bennion