Bimetallic silver-gold film waveguide surface plasmon resonance sensor
Ong, Biow Hiem
Tjin, Swee Chuan
Date of Issue2007
School of Electrical and Electronic Engineering
Photonics Research Centre
It is desirable that a surface plasmon resonance (SPR) sensor is highly sensitive to binding interactions within the sensing region, generate evanescent fields with long penetration depths, and utilize a metal film that is very stable even in extreme environmental conditions. In this study, we present the first example of a wavelength-modulated waveguide SPR sensor with a bimetallic silver-gold film for surface plasmon excitation. The underlying silver yields better evanescent field enhancement of the sensing surface, while the overlying gold ensures that the stability of the metallic film is not compromised. It is shown experimentally that in terms of dλ/dn, the bimetallic film waveguide SPR configuration has a sensitivity of 1232 nm/RIU, greater than two times improvement from the 594 nm/RIU achievable with single gold film waveguide SPR sensor. The higher sensitivity, compact nature, and better evanescent field enhancement of this configuration provides the potential to biosensing applications.
DRNTU::Engineering::Electrical and electronic engineering::Optics, optoelectronics, photonics
Fiber and integrated optics
© 2007 Taylor & Francis This is the author created version of a work that has been peer reviewed and accepted for publication by Fiber and Integrated Optics, Taylor & Francis. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [DOI: http://dx.doi.org/10.1080/01468030701347106].