Développement de capteurs à fibre optique basés sur la résonance ...

Résumé Général (en anglais)
Preface
Developments of the Fiber-Optic Sensors
Based on Surface Plasmon Resonance
for Physical, Chemical and Biological Detection
It is well known that surface plasmon resonance (SPR) of the surface electromagnetic
wave can be used as a sensitive optical probe to the slight variations occurring in the
proximity of the metal/dielectric interface. The prism-based Kretschmann configuration is
traditionally employed to excite and detect the SPR. In 1993, the first fiber-optic based SPR
sensor was realized by R.C.Jorgenson and S.S.Yee and then commercialized by Biacore
Company (Sweden). The SPR fiber-optic sensor offers a number of advantages such as small
size, low cost and feasibility in remote sensing over the bulk Kretschmann system. A simpler
SPR multimode fiber-optic sensor using oblique injection of the collimated monochromatic
light has been developed at the TSI laboratory, Jean Monnet University in Samt-Etienne,
France since 1996. Using silver to support SPR at the light wavelength of 670nm, this fiberoptic
sensor was characterized as a refractometer operating in the index range of 1.35-1.40.
This dissertation consists of five articles aimed to develop this kind of fiber-optic sensor
for physical, chemical and biological applications. The first article is devoted to drop down
the range of measurable indices in order to be capable of performing in most practical
chemical and biochemical systems whose refractive indices are 1.33-1.36. The relations
between the structural and material parameters of the multilayered configuration for the
excitation of SPR at certain wavelength have been theoretically derived. Sol-gel technique is
applied to fabricate the Zirconium acetate overlay as thin as some ten nanometers. The
reliability is improved by preventing the oxidation of silver using a self-assembled monolayer
(SAM) of long chain acid thiol. This article has been submitted to Thin Solid Films. Accepted
by Sensors & Actuators A, the spatial variations of the electric field vector during the
propagation of the skew rays in the multimode fiber are investigated in the second article. An
accurate 3D model has been established so that the experimental phenomena, which first
demonstrate the influences of the polarization direction of the incident light with respect to
the input end face of the fiber, can be consistently explained. The sensing signals coming
from such as the adsorption of a very thin dielectric layer on metal surface or the slight
variation of the refractive index in the monitored bulk medium are ready to be quantitatively
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