Title :
Ultrasensitive Refractive Index Sensor Based on Microfiber-Assisted U-Shape Cavity
Author :
Shecheng Gao ; Weigang Zhang ; Zhiyong Bai ; Hao Zhang ; Pengcheng Geng ; Wei Lin ; Jieliang Li
Author_Institution :
Key Lab. of Opt. Inf. Sci. & Technol., Nankai Univ., Tianjin, China
Abstract :
A novel in-fiber Mach-Zehnder interferometer formed by a microfiber-assisted U-shape cavity (MFA-USC) with ultrahigh refractive index (RI) sensitivity and an ultra-wide RI measurement range is demonstrated. The MFA-USC is fabricated by splicing a section of micro-fiber (diameter is ~ 63 μm, length is 688 μm) tapered from single-mode fiber (SMF) between two sections of SMF with designed fiber geometry relationship. An ultrahigh sensitivity (higher than 126 000 nm/RIU at a RI of 1.445) within a RI range 1.320-1.446 and 1.462-1.738 has been experimentally achieved. This sensitivity is the highest ever reported to date to the best of our knowledge.
Keywords :
Mach-Zehnder interferometers; fibre optic sensors; micro-optics; microsensors; optical fibre fabrication; refractive index measurement; designed fiber geometry relationship; in-fiber Mach-Zehnder interferometer; microfiber-assisted U-shape cavity; optical fibre fabrication; single-mode fiber; size 688 mum; ultrasensitive refractive index sensor; Cavity resonators; Liquids; Optical fiber sensors; Optical fibers; Sensitivity; Temperature sensors; Mach–Zehnder interferometer; microfiber; optical fiber sensor; refractive index measurement;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2013.2274492
