Open AccessNumerical analysis of a near-infrared plasmonic refractive index sensor with high figure of merit based on a fillet cavity
Author(s) -
Lei Chen,
Yumin Liu,
Zhongyuan Yu,
Dong Wu,
Rui Ma,
Yang Zhang,
Han Ye
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.009975
Subject(s) - figure of merit , optics , refractive index , materials science , plasmon , full width at half maximum , nanophotonics , transmittance , wavelength , fabry–pérot interferometer , optoelectronics , infrared , physics
A near-infrared plasmonic refractive index (RI) sensor with figure of merit (FOM) as high as 124.6 is proposed and investigated numerically. The RI sensing is realized by employing the linear relation between resonant wavelength and RI of the material under detecting. Based on the fillet cavity coupled with two metal-insulator-metal waveguides, transmission efficiency (T) and optical resolution (FWHM) of the RI sensor are both improved to a great extent with T = 95% and FWHM = 12nm, keeping acceptable wavelength sensitivity of 1496nm/RIU within the near-infrared region. In addition, a sensitivity as high as 3476nm/RIU is obtained by optimizing the shape and size of fillet cavity. In general, the high FOM, transmittance and sensitivity achieved by our design may get further applications in biomedical science and nanophotonic circuits.