Refractive index sensing of double Fano resonance excited by nano-cube array coupled with multilayer all-dielectric film

Abstract

We propose a hybrid structure of a nano-cube array coupled with multilayer full-dielectric thin films for refractive index sensing. In this structure, discrete states generated by two-dimensional grating and continuous states generated by a photonic crystal were coupled at a specific wavelength to form two Fano resonances. The transmission spectra and electric field distributions of the structure were obtained via the finite-difference time-domain method. We obtained the optimal structural parameters after optimizing the geometrical parameters. Under the optimal parameters, the figure of merit (FOM) values of the two Fano resonances reached 1.7 × 104 and 3.9 × 103, respectively. These results indicate that the proposed structure can achieve high FOM refractive index sensing, thus offering extensive application prospects in the biological and chemical fields.

The Light Absorption Enhancement in Graphene Monolayer Resulting from the Diffraction Coupling of Surface Plasmon Polariton Resonance

“…The array periods of the Au nanospheres are p x and p y along the x-axis and the y-axis directions, respectively. Each Au nanosphere is able to support the excitation of the localized surface plasmon polariton resonance [52][53][54][55][56]. The SiO 2 substrate and the SiO 2 cover layer have a constant refractive index of 1.45.…”

“…support the excitation of the localized surface plasmon polariton resonance [52][53][54][55][56]. The SiO2 substrate and the SiO2 cover layer have a constant refractive index of 1.45.…”

Thermal tuning of terahertz metamaterial absorber properties based on VO2

“…Such a design would have great potential in wide-ranging applications, including photochemical energy harvesting, stealth devices, thermal emitters, etc. [28][29][30][31]…”

Surface plasmon polaritons enhanced magnetic plasmon resonance for high-quality sensing

“…Finally, we study the optical sensing performance of the designed metamaterials. Because the position and intensity of the reflection spectrum will vary with the change of external refractive index, we use the definitions of sensitivity and figure of merit to characterize the sensing performance: [53][54][55][56][57][58][59][60][61][62] Note that, although we did not optimize the optical metamaterials for sensing, the high sensitivity and the figure of merit obtained here have reached the highest level of the recently reported plasmon sensing. 62) In summary, we have proposed that the strong coupling state of MP and SPPs can be realized in SRRs-based metamaterials, and the ultra-narrow hybrid mode with FWHM of about 2.5 nm is obtained, which greatly enhances the magnetic response.…”