Numerical and analytical evaluations of the sensing sensitivity of waveguide mode in one-dimensional metallic gratings

Dangyuan Lei, Jones T K Wan, Hock Chun Ong

Research output: Journal article publicationJournal articleAcademic researchpeer-review

8 Citations (Scopus)


We study numerically and analytically the refractive index sensing sensitivities of surface plasmon (S SP) and waveguide (S WG) modes arising from one-dimensional Au gratings. By using rigorous coupled wave analysis, we find that while S SP is mainly controlled by the periodicity of the grating, the shape of the groove governs S WG. As a result, it is possible to increase S WG to 1000nm/RIU and figure of merit to 24 by tailoring the height and width of the groove. Finally, a simple analytical expression is derived to describe S WG and it agrees well with the numerical data. This easy-to-use expression not only reveals the origin of waveguide mode sensitivity, but also provides useful guidance for the theoretical design and experimental realization of high-sensitivity metallic-gratings-based biosensors.
Original languageEnglish
Article number275501
Issue number27
Publication statusPublished - 11 Jul 2012
Externally publishedYes

ASJC Scopus subject areas

  • Bioengineering
  • Chemistry(all)
  • Electrical and Electronic Engineering
  • Mechanical Engineering
  • Mechanics of Materials
  • Materials Science(all)

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