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

Volume

25

Issue

18

fYear

2013

fDate

Sept.15, 2013

Firstpage

1815

Lastpage

1818

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;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2013.2274492

Filename

6568878