Plasmon enhanced photovoltaic effect in metallically nanomodified photocells

Plasmons in noble metallic nanoparticles can be used in order to increase efficiency of energy transfer in solar cells of various configurations, mainly in diode-type setups. The origin of plasmonic effect is still not fully recognized and one of the important contributions to photocurrent enhancement results from the inclusion of non-conserved momentum interband transition in semiconductor as a consequence of absence of translational invariance in nanomodified system. We consider energy transfer efficiency via plasmons in nanoparticles and its dependency of nanoparticle radius. Fully-analytical, semiclassical approach for plasmons in spherical geometry is applied and efficiency of near-field absorption in semiconductor is estimated upon Fermiʹs golden rule. Finally, we link our results with experimental measurements of photocurrent gain in semiconductor silicon-diode setup with gold nanoparticles, which occur in positive qualitative agreement with the theoretical predictions.