About the Journal :
The radiation efﬁciency of nano-antennas is a key parameter in the emerging ﬁeld of IR and optical energy harvesting. This parameter is the ﬁrst factor in the total efﬁciency product by which nano-antennas are able to convert incident light into useful energy. This efﬁciency is investigatedintermsofthemetalusedasconductorandthedimensionsofthenano-antenna. Theresultssetupperboundsforanypossibleprocesstransforminglightintoelectricalenergy. These upper bounds are the equivalent of the theoretical upper bounds for the efﬁciency of conventionalsolarcells.Silvershowsthehighestefﬁciencies,bothinfreespaceandontopofa glass (SiO2) substrate, with radiation efﬁciencies near or slightly above 90%, and a total solar powerharvestingefﬁciencyofabout60–70%.Thisisconsiderablyhigherthanconventionalsolar cells.Itisfoundthatﬁne-tuningofthedipoledimensionsiscrucialtooptimizetheefﬁciency. & 2012 Elsevier Ltd. All rightsreserved.
Keywords:Harvesting; Energy; Solar; Nano-antenna.