Open AccessWavelength-selective plasmonic sensor based on chirped-pitch crossed surface relief gratings
Author(s) -
Yazan Bdour,
Carlos Escobedo,
Ribal Georges Sabat
Publication year - 2019
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.27.008429
Subject(s) - materials science , optics , surface plasmon resonance , polarizer , wavelength , refractive index , grating , polarization (electrochemistry) , surface plasmon , diffraction grating , optoelectronics , plasmon , nanoparticle , physics , nanotechnology , chemistry , birefringence
Two-dimensional chirped-pitch crossed surface relief gratings (CP-CSRGs) were fabricated on azobenzene-functionalized thin films using a simple two-step procedure. The resulting gratings had a constant pitch in one direction and a varying (chirped) pitch in the orthogonal direction. They were coated with silver and tested for their ability to change the polarization of surface plasmon resonance (SPR) signals, when placed between crossed polarizers. It was observed that several different bandwidths of SPR wavelengths are excitable using a single device, making CP-CSRGs suitable as next generation SPR-based sensors. The SPR wavelengths shifted as much as 10.5 nm/mm along the chirped grating, and a maximum sensitivity of 778.6 nm/RIU was obtained when detecting the refractive index change of various concentrations of aqueous sucrose solutions.