Abstract
In this Letter, we demonstrate 8°-tilted fiber Bragg grating (TFBG) inscription in single-mode step-index TOPAS/ZEONEX polymer optical fibers (POFs) using a 520 nm femtosecond laser and the line-by-line (LbL) writing technique. As a result of the tilt angle and the fiber refractive index, a large spectral range of cladding mode resonances covering 147 nm is obtained. The evolution of the transmitted spectrum is analyzed as a function of the surrounding refractive index (SRI) in a large range from 1.30 to 1.50. The cutoff cladding mode shows a refractive index sensitivity of 507 nm/RIU (refractive index unit). For single-resonance tracking near the cutoff mode, the sensitivity is at least 6 nm/RIU, depending on the exact wavelength position of the cladding modes. The main originality of our work is that it produces, for the first time, to the best of our knowledge, a TFBG in POF that operates in the refractive index range of aqueous solutions. The sensing capability for a large range of refractive index values is also relevant for (bio)chemical sensing in different media.
© 2023 Optica Publishing Group
Full Article | PDF ArticleMore Like This
Bonan Liu, Kaiming Yang, Changrui Liao, Zhihao Cai, Yifan Liu, Bing Sun, and Yiping Wang
Opt. Lett. 46(9) 2204-2207 (2021)
Xuehao Hu, Chi-Fung Jeff Pun, Hwa-Yaw Tam, Patrice Mégret, and Christophe Caucheteur
Opt. Lett. 39(24) 6835-6838 (2014)
Xuehao Hu, Zhen Chen, Xin Cheng, Rui Min, Hang Qu, Christophe Caucheteur, and Hwa-Yaw Tam
Opt. Lett. 47(2) 249-252 (2022)