Title :
Integrated optical bio-sensor based on pure surface plasmon-polariton excited by a waveguide grating
Author :
Baiad, Mohamad Diaa ; Tripathi, Saurabh Mani ; Kumar, Arun ; Nenova, Galina ; Kashyap, Raman
Author_Institution :
Dept. of Electr. Eng., Ecole Polytech. de Montreal, Montreal, QC, Canada
Abstract :
In this paper, we present a theoretical model and the characteristics of a refractive index sensor based on pure surface plasmon-polariton (SPP) excited by a properly designed waveguide Bragg gratings (WBG) or long period gratings (LPG). The gratings are imprinted in a waveguide layer and we propose the potential of a buried waveguide fabricated by a novel method for SPP bio-sensing using a continues-wave (CW) CO2 laser. The pure SPP is propagating in an optimized 5-layer structure which has a metal thickness of 20 nm and separated from the waveguide layer by a dielectric cladding which has thickness of 0.5 μm. As a result, LPG based sensor is more sensitive to changes in the sensed medium refractive index and requires much shorter gratings length for a given sensitivity than the WBG based one. The proposed sensor is highly sensitive and free from any moving parts and can be used as bio/chemical sensor.
Keywords :
Bragg gratings; biosensors; carbon compounds; chemical sensors; optical sensors; physiological models; polaritons; refractive index; surface plasmons; CO2; biochemical sensor; continues-wave laser; dielectric cladding; integrated optical biosensor; long period gratings; medium refractive index; optimized 5-layer structure; pure surface plasmon-polariton; refractive index sensor; size 20 nm; waveguide Bragg gratings; waveguide layer; Gratings; Integrated optics; Optical refraction; Optical sensors; Optical surface waves; Sensitivity; grating; laser written optical waveguides; surface plasmon-polariton;
Conference_Titel :
Fibre and Optical Passive Components (WFOPC), 2011 7th Workshop on
Conference_Location :
Montreal, QC
Print_ISBN :
978-1-4577-0861-9
DOI :
10.1109/WFOPC.2011.6089672
