Dual-band Dielectric Light-harvesting Nanoantennae Made by Nature

Mechanisms to use nanoparticles to separate sunlight into photovoltaic useful range and thermally useful range to increase the efficiency of solar cells and to dissipate heat radiatively are discussed based upon lessons we learnt from photosynthesis. We show that the dual-band maxima in the absorption spectrum of bacterial light harvestors not only are due to the bacteriochlorophylls involved but also come from the geometry of the light harvestor. Being able to manipulate these two bands arbitrarily enables us to fabricate the nanoparticles required. Such mechanisms are also useful for the design of remote power charging and light sensors.