Plasmonic refractive index sensitivity of ellipsoidal Al nanoshell: Tuning the wavelength position and width of spectral dip

摘要: Abstract The absorption spectra of ellipsoidal Al nanoshell show a distinct dip due to the two adjacent localized surface plasmon resonance (LSPR) peaks corresponding longitudinal from inner and outer surfaces shell. Both position its linewidth are sensitive refractive index surrounding. And sensitivity could be well tuned by shell thickness, aspect ratio, nonuniformity dielectric environment. By comparing with wavelength, width is more geometry nanoshell. It has been found that widening speed spectrum as function environmental greatly enlarged increasing ratio thickness. also interesting note changes non-monotonously when large constant core thick transverse physical mechanism attributed different shift speeds between symmetric antisymmetric LSPR along direction. This environment dependent-spectrum presents new sensing picture based on tuning position.