Novel optical-waveguide sensing platform based on input grating coupler

Published

Conference Paper

Silicon oxynitride optical waveguides with a grating coupler were used for a label-free detection approach that measures the change of refractive index at the grating surface. Two approaches were used for the grating fabrication: (i) commercially available linear gratings were used as stamps for imprint lithography and the pattern was transferred by dry-etching; (ii) polystyrene microspheres self-assembly in an ordered close-packed array was exploited to obtain a two-dimensional grating with hexagonal symmetry. Optical coupling into slab waveguides of both visible (633nm) and tunable infrared (1550 nm) lasers was characterized as a function of incident angle in a custom-made automated apparatus. Sensitivity to different aqueous solutions was demonstrated with low loss waveguides fabricated using low-frequency plasma-enhanced chemical vapor deposition. The exploitation of the tunability of telecom infrared lasers and of the two-dimensional hexagonal grating coupler has the ultimate goal of providing a high performance, compact sensor that does not require mechanical moving parts.

Full Text

Duke Authors

Cited Authors

  • Grego, S; Naskar, S; Patel, AM; Huffman, A; Bower, CA; Stoner, BR

Published Date

  • May 25, 2006

Published In

Volume / Issue

  • 6123 /

International Standard Serial Number (ISSN)

  • 0277-786X

International Standard Book Number 10 (ISBN-10)

  • 0819461652

International Standard Book Number 13 (ISBN-13)

  • 9780819461650

Digital Object Identifier (DOI)

  • 10.1117/12.646302

Citation Source

  • Scopus