This damping is significantly more pronounced than for metallic nanoparticles – more than 60 % here compared to approximately 20 % in the corresponding case of metals (see also Additional file 4:
Figure S4). Figure 8 Angular scattering distribution and scattering cross section for a dielectric nanoparticle at an interface. (a) Angular distribution of light scattered from an r = 170 nm, n = 2, k = 0 dielectric nanoparticle in air, i.e., buy VX-809 n = 1 (blue), at an air/n = 1.5 interface (turquoise) and at an air/n = 3 interface (magenta) (incident light from the top); (b) shows the according scattering cross sections from which the wavelengths of the quadrupole resonance were chosen for the representation of the angular distributions in (a), i.e., 502, 490, and 502 nm. Finally, with the integration of a substrate, leaky modes may emerge for the dielectric nanoparticles that, like enhanced near fields, can promote absorption in the underlying layer. Figure 9 shows the electromagnetic near field distribution around the dielectric nanoparticle with n = 2,
k = 0, and r = 170 nm when embedded half XL184 in vitro in air and half in the substrate with (subfigure a) n = 1.5 and (subfigure b) n = 3. For the case of the low-index substrate, we find stronger forward scattering, which is in agreement with the angular scattering distributions, and the local field in the direct forward direction is enhanced and appears more
pronounced than for the nanoparticle in air, compare Figure 4b. However, for the high-index substrate, the local electromagnetic field is more concentrated inside the nanoparticle or directed sidewards which can be correlated to the angular scattering distribution as well. Seeing these two cases together, we can conclude that leaky modes from dielectric nanoparticles occur if the substrate refractive index is lower than the one of the Sulfite dehydrogenase nanoparticles and that the local fields are more pronounced in the material with the lower refractive index (which also may be the nanoparticle if the substrate has a higher refractive index). Figure 9 Near field distributions of a dielectric nanoparticle at an interface. Electromagnetic field around a dielectric nanoparticle n = 2, k = 0, and r = 170 nm, embedded half in air, half in a substrate with refractive index (a) n = 1.5 and (b) n = 3. The dipole, the quadrupole, and the hexapole modes are shown for the wavelengths of 680/816 nm, 490/502 nm, and 396/346 nm, respectively, which correspond to the maxima in scattering, see Figure 8b (incident light from the top). A high angular scattering distribution is present for metallic nanoparticles in selleck chemical vacuum and can easily be reinforced by the integration of a substrate without showing significant losses in overall scattering efficiency.