A silicon photonic biosensor using phase‐shifted Bragg gratings in slot waveguide. Issue 10 (11th April 2013)

• Record Type: Journal Article
• Authors: Wang, Xu; Flueckiger, Jonas; Schmidt, Shon; Grist, Samantha; Fard, Sahba T.; Kirk, James; Doerfler, Matt; Cheung, Karen C.; Ratner, Daniel M.; Chrostowski, Lukas
• Is Part Of: Journal of biophotonics. Volume 6:Issue 10(2013:Oct.)
• Page Start: 821
• Page End: 828
• Publication Date: 2013-04-11
• Subjects: Photonics -- Periodicals; Optical materials -- Periodicals; Optics -- Periodicals; Medical instruments and apparatus -- Periodicals; 621.3605
• DOI: 10.1002/jbio.201300012
• Languages: English
• ISSNs: 1864-063X

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>We present a novel silicon photonic biosensor using phase‐shifted Bragg gratings in a slot waveguide. The optical field is concentrated inside the slot region, leading to efficient light‐matter interaction. The Bragg gratings are formed with sidewall corrugations on the outside of the waveguide, and a phase shift is introduced to create a sharp resonant peak within the stop band. We experimentally demonstrate a high sensitivity of 340 nm/RIU measured in salt solutions and a high quality factor of 1.5 × 10⁴, enabling a low intrinsic limit of detection of 3 × 10^–4 RIU. Furthermore, the silicon device was fabricated by a CMOS foundry, facilitating high‐volume and low‐cost production. Finally, we demonstrate the device's ability to interrogate specific biomolecular interactions, resulting in the first of its kind label‐free biosensor. (© 2013 WILEY‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)</p> </abstract>