Refractive Index Sensing Using Quasi One-Dimensional Nanoslit Arrays

Article · July 2009with9 Reads
DOI: 10.1021/nl900773m · Source: PubMed
This letter describes the optical properties of quasi one-dimensional (1D) Au nanoslit arrays on a microscale pitch. The transmission spectra exhibited multiple minima that were well characterized by 1D surface plasmon polariton Bloch wave modes. We found that all higher order modes showed a linear response to small changes of refractive index (RI) with sensitivities up to 560 nm per RI unit, which is comparable to that of two-dimensional nanohole arrays. By calibrating the RI response of the nanoslit arrays, we could use the multiple modes to determine the RI of unknown, nonabsorbing solutions.
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December 2008 · Proceedings of the National Academy of Sciences · Impact Factor: 9.67
Surface plasmon polaritons (SPPs) are responsible for exotic optical phenomena, including negative refraction, surface enhanced Raman scattering, and nanoscale focusing of light. Although many materials support SPPs, the choice of metal for most applications has been based on traditional plasmonic materials (Ag, Au) because there have been no side-by-side comparisons of the different materials... [Show full abstract]
November 2008 · Annual Review of Physical Chemistry · Impact Factor: 16.84
This review focuses on nanofabrication tools, based on soft lithography, which can generate a wide range of noble-metal structures with exceptional optical properties. These techniques offer a scalable and practical approach for producing arrays of complementary plasmonic structures (nanoholes and nanoparticles) and, in addition, expand the possible architectures of plasmonic materials because... [Show full abstract]
September 2007 · Nature Nanotechnology · Impact Factor: 34.05
The interaction of light with surface plasmons--collective oscillations of free electrons--in metallic nanostructures has resulted in demonstrations of enhanced optical transmission, collimation of light through a subwavelength aperture, negative permeability and refraction at visible wavelengths, and second-harmonic generation from magnetic metamaterials. The structures that display these... [Show full abstract]
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