Design and fabrication of a waveguide-coupled prism device for surface plasmon resonance sensor

A novel waveguide-coupled prism device as a surface plasmon resonance senso r has been developed. The waveguide was fabricated by depositing Ag, SiO2, and Au thin films in this order on a prism. The device demonstrated a sharp absorption in the light reflectance curve due not only to the insertion of polarized light where electric field was parallel to the reflection plane (P-wave) but to that perpendicular to the reflection plane (S-wave). The ex perimental reflectance curves for both P- and S-waves were well predicted b y the Fresnel formulas. The former and the latter absorptions are due to su rface plasmon resonance and the attenuation of propagating light through th e waveguide by the repetitive absorption at the metal/SiO2 boundary, respec tively. (C) 2000 Elsevier Science S.A. All rights reserved.