High-resolution surface plasmon resonance sensor based on linewidth-optimized nanohole array transmittance

Department of Electrical and Computer Engineering, University of California, San Diego, San Diego, California, United States
Optics Letters (Impact Factor: 3.18). 06/2006; 31(10):1528-30. DOI: 10.1364/OL.31.001528
Source: PubMed

ABSTRACT A high spectral resolution, 2D nanohole-array-based surface plasmon resonance sensor that operates at normal or near normal incidence--facilitating high spatial resolution imaging--is presented. The angular and spectral transmittance of the structure is modified from a Fano type to a pure Lorentzian line shape with a parallel and orthogonal polarizer-analyzer pair. This change leads to a linewidth narrowing that maximizes the sensor resolution, which we show to be of O(10(-5)) refractive index units (RIU). We estimate the potential of this system of O(10(-6)) RIU under optimal conditions.

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