title: Silicon-on-insulator guided mode resonant grating for evanescent field molecular sensing.
abstract: We present experimental and theoretical results of label-free molecular sensing using the transverse magnetic mode of a 0.22 mum thick silicon slab waveguide with a surface grating implemented in a guided mode resonance configuration. Due to the strong overlap of the evanescent field of the waveguide mode with a molecular layer attached to the surface, these sensors exhibit high sensitivity, while their fabrication and packaging requirements are modest. Experimentally, we demonstrate a resonance wavelength shift of approximately 1 nm when a monolayer of the protein streptavidin is attached to the surface, in good agreement with calculations based on rigorous coupled wave analysis. In our current optical setup this shift corresponds to an estimated limit of detection of 0.2% of a monolayer of streptavidin.
authors.affiliation: Institute for Microstructural Sciences, National Research Council Canada, Ottawa, Ontario, K1A 0R6. jens.schmid@nrc-cnrc.gc.ca
authors.forename: J H
authors.initials: JH
authors.lastname: Schmid
authors.forename: W
authors.initials: W
authors.lastname: Sinclair
authors.forename: J
authors.initials: J
authors.lastname: García
authors.forename: S
authors.initials: S
authors.lastname: Janz
authors.forename: J
authors.initials: J
authors.lastname: Lapointe
authors.forename: D
authors.initials: D
authors.lastname: Poitras
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: T
authors.initials: T
authors.lastname: Mischki
authors.forename: G
authors.initials: G
authors.lastname: Lopinski
authors.forename: P
authors.initials: P
authors.lastname: Cheben
authors.forename: A
authors.initials: A
authors.lastname: Delâge
authors.forename: A
authors.initials: A
authors.lastname: Densmore
authors.forename: P
authors.initials: P
authors.lastname: Waldron
authors.forename: D-X
authors.initials: DX
authors.lastname: Xu
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008027:Light; D015336:Molecular Probe Techniques / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D012825:Silicon / Q000737:chemistry* / Q000528:radiation effects; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D014159:Transducers
chemical_list: D012825:Silicon