Paper Info
Title
Modeling of a Single-Notch Microfiber Coupler for High-Sensitivity and Low Detection-Limit Refractive Index Sensing.
Abstract
A highly sensitive refractive index sensor with low detection limit based on an asymmetric optical microfiber coupler is proposed. It is composed of a silica optical microfiber and an As2Se3 optical microfiber. Due to the asymmetry of the microfiber materials, a single-notch transmission spectrum is demonstrated by the large refractive index difference between the two optical microfibers. Compared with the symmetric coupler, the bandwidth of the asymmetric structure is over one order of magnitude narrower than that of the former. Therefore, the asymmetric optical microfiber coupler based sensor can reach over one order of magnitude smaller detection limit, which is defined as the minimal detectable refractive index change caused by the surrounding analyte. With the advantage of large evanescent field, the results also show that a sensitivity of up to 3212 nm per refractive index unit with a bandwidth of 12 nm is achieved with the asymmetric optical microfiber coupler. Furthermore, a maximum sensitivity of 4549 nm per refractive index unit can be reached while the radii of the silica optical microfiber and As2Se3 optical microfiber are 0.5 mu m and a 0.128 mu m, respectively. This sensor component may have important potential for low detection-limit physical and biochemical sensing applications.
Year
DOI
Venue
2016
10.3390/s16050672
SENSORS
Keywords
Field
DocType
optical microfiber sensors,asymmetric coupler,low detection limit
Detection limit,Evanescent wave,Sensing applications,Optics,Radius,Bandwidth (signal processing),Microfiber,Engineering,Order of magnitude,Refractive index
Journal
Volume
Issue
ISSN
16
5.0
1424-8220
Citations 
PageRank 
References 
0
0.34
1
Authors
5
Name
Order
Citations
PageRank
Jiali Zhang183.23
Lei Shi200.68
Song Zhu314919.42
Xinbiao Xu400.34
Xinliang Zhang5610.01