Figure 5

(a) Transmittance spectra of a 2 μm thick Si, a 120 nm Au sphere and core-shell nanoparticles with different coating thickness t on the 2 μm thick Si substrates. (b) Comparison of absorption spectra among a 2 μm thick Si, a 120 nm Au sphere and core-shell nanoparticles with a 60 nm coating on the 2 μm thick Si substrates and the P is set as 400 nm. (c) Global tilt solar spectrum, together with graphs that illustrate the solar energy absorbed in a 2 μm thick Si film (assuming single-pass absorption and no reflection coating), a 2 μm thick Si film with a 120 nm Au sphere (P = 400 nm) and a 2 μm thick Si film with a core-shell nanoparticle (t = 60 nm, P = 400 nm). (d) Angular scattering of a core-shell nanoparticle on a 2 μm thick Si film under 983 nm illumination (t = 40 nm, P = 400 nm), indicating the suppressed backward scattering and the favoured forward scattering.