Localized surface plasmon resonance properties of two-layered gold nanowire: Effects of geometry, incidence angle, and polarization

Abstract

The extinction spectra of two-layered gold nanowires (TGNWs) have been calculated by using the vector wave function method. When the polarization direction of incident light is perpendicular to the incidence plane, it is found with increasing the incidence angle that the dipole resonance wavelength of TGNW shows a decrease, whereas the full-width at half-maximum (FWHM) for the dipole resonance peak decreases. With decreasing the shell thickness or increasing the dielectric constant of the inner core, the localized surface plasmon resonance (LSPR) of TGNW shows a distinct redshift, whereas the FWHM of the dipole peak increases. When the polarization direction of incident light is parallel to the incident plane, the LSPR in TGNW gradually appears with decreasing incidence angle and can be modulated by the geometry. We have ascribed the variations of the LSPR in TGNW to the competition between the variations of phase retardation and oscillation electrons.

Geometrical parameters controlled focusing and enhancing near field in infinite circular metal-dielectric multilayered cylinder

“…2(b). It is obvious to find the LFF spectra only have two distinct peaks corresponding to jx þ À i and jx À À i plasmon mode, and the local field factor in the middle dielectric wall has been greatly enhanced to 80 when [R 1 ,R 2 ,R 3 ] ¼ [5,7,25] nm (thick tube) and [e 2 , e 4 ] ¼ [1,4]. In Fig.…”

“…The local field factor in gold nanotube is found to be sensitive to the radius and dielectric constant of the inner core. 25 Moreover, the intense local field has been focused into the gold nanohole when the nanotube has a thick gold wall. 15 Baida et al reported the mode propagation and attenuation properties in a nanometric coaxial waveguide in real metal.…”

“…In Fig. 2(a), [R 1 ,R 2 ,R 3 ] ¼ [5,22,25] nm (thin tube) and [e 2 , e 4 ] ¼ [4,1]; thus, the middle dielectric wall has a large thickness and a large dielectric constant. The absorption spectrum displays three separated peaks corresponding to jx À þ i, jx þ À i, and jx À À i plasmon hybridization modes, respectively.…”

Plasmon–exciton induced transparency in plexcitonic Ag–CuCl-coated nanowires and associated arrays

“…For TE wave, the scattering efficiency Q sca,I can be expressed as [32] where a nI and b nI are the scattering coefficients. a 0I and a 1I correspond to the magnetic (MD) and electric (ED) dipole modes, respectively [33].…”

“…The incident light interacting with an infinite ACNW can be described by the scattering theory [32]. The electromagnetic waves are expanded by using vector cylindrical harmonic functions, and then, Maxwell's boundary conditions…”