Abstract
We propose a plasmonic nanosensor based on Fano resonance in the strong-confinement metal-dielectric-metal waveguide side-coupled with a pair of nanoresonators. Due to the coherent interference of the splitting discrete and quasi-continuum modes, the reflection spectrum possesses a sharp asymmetric Fano resonance dip, which is dependent on the cavity-cavity phase and the refractive index change of the dielectric. The physical features contribute to a highly efficient plasmonic sensor for refractive index sensing. The nanosensor yields a sensitivity of ∼900 nm/ RIU and a figure of merit of ∼500, remarkable values compared with those of plasmonic sensors supported by perfect absorbers.
Original language | English |
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Pages (from-to) | 3780-3782 |
Number of pages | 3 |
Journal | Optics Letters |
Volume | 37 |
Issue number | 18 |
DOIs | |
State | Published - 15 Sep 2012 |
Externally published | Yes |