Incident angle dependence of absorption enhancement in plasmonic solar cells.

The enhancement of solar light absorption in a solar cell is a challenging issue. In this article we show that in a thin-film silicon solar cell covered with silver nanoparticles on the surface, the absorption of the incident light can be particularly enhanced at certain angular range and wavelength. Such absorption enhancements are associated with the resonant localized surface plasmon (LSP) modes of the nanoparticle and nanoparticle-induced local Fabry-Perot (FP) modes. Our simulations suggest that the spectral shift of the LSP modes due to changing the incident angle leads to an incident-angle-sensitive absorption enhancement of the solar cell. Selecting the incident angle in a well-defined range of 0° to 35° is essential for optimizing the performance of a thin-film solar cell.