Plasmons in metallic nanospheres: Towards efficiency enhancement of metallic nano-modified solar cells

Abstract An explanation of a large plasmon-induced PV efficiency enhancement of metallically surface-modified photo-cell is given by inclusion of all indirect inter-band electron transitions in semiconductor due to near-field coupling with plasmon radiation of a nano-scale metallic components. The model of nanosphere plasmon is formulated (of RPA-type, adjusted to large clusters) for both surface and volume modes. Damping of plasmons is analyzed including irradiation losses due to the Lorentz friction. Probability of the interband transition in substrate semiconductor caused by the coupling with plasmons in near-field regime turns out to be larger by 4-orders (in an idealised atomic regime) than for coupling of electrons with planar-wave photons. Inclusion of proximity and interference effects allows for explanation of photo-current growth measured in experimental metallically modified photo-diode systems.