Open AccessPlasmonic sensors based on tilted Bragg gratings in multicore optical fibers
Author(s) -
Angel Ortega-Gomez,
Médéric Loyez,
Maxime Lobry,
Karima Chah,
Joseba Zubía,
Joel Villatoro,
Christophe Caucheteur
Publication year - 2021
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.430181
Subject(s) - materials science , fiber bragg grating , optics , refractometer , surface plasmon resonance , plasmon , optical fiber , optoelectronics , fiber optic sensor , surface plasmon , refractometry , sensitivity (control systems) , refractive index , nanotechnology , nanoparticle , wavelength , physics , engineering , electronic engineering
Bare and gold-coated tilted fiber Bragg gratings (TFBGs) can nowadays be considered as a mature technology for volume and surface refractometric sensing, respectively. As for other technologies, a continuous effort is made towards the production of even more sensitive sensors, thereby enabling a high-resolution screening of the surroundings and the possible detection of rare events. To this aim, we study in this work the development of TFBG refractometers in 4-core fibers. In particular, we show that the refractometric sensitivity of the cut-off mode can reach 100 nm/RIU for a bare grating. Using another demodulation method, a tenfold sensitivity increase is obtained when tracking the extremum of the SPR (surface plasmon resonance) envelope for a gold-coated TFBG configuration. Immobilization of DNA probes was performed as a proof-of-concept to assess the high surface sensitivity of the device.