Open AccessEnhancing the sensitivity of plasmonic optical fiber sensors by analyzing the distribution of the optical modes intensity
Author(s) -
Karim Vindas,
Arnaud Buhot,
Thierry Livache,
Patrick Garrigue,
Nešo Šojić,
Loïc Leroy,
Élodie Engel
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.399856
Subject(s) - refractive index , optics , plasmon , sensitivity (control systems) , optical fiber , fiber optic sensor , light intensity , materials science , intensity (physics) , core (optical fiber) , reflection (computer programming) , focus (optics) , optoelectronics , computer science , physics , electronic engineering , engineering , programming language
Improving the sensitivity of plasmonic optical fiber sensors constitutes a major challenge as it could significantly enhance their sensing capabilities for the label-free detection of biomolecular interactions or chemical compounds. While many efforts focus on developing more sensitive structures, we present here how the sensitivity of a sensor can be significantly enhanced by improving the light analysis. Contrary to the common approach where the global intensity of the light coming from the core is averaged, our approach is based on the full analysis of the retro-reflected intensity distribution that evolves with the refractive index of the medium being analyzed. Thanks to this original and simple approach, the refractive index sensitivity of a plasmonic optical fiber sensor used in reflection mode was enhanced by a factor of 25 compared to the standard method. The reported approach opens exciting perspectives for improving the remote detection as well as for developing new sensing strategies.