Plasmon coupling for efficiency enhancement in energy harvesting
Plasmonic solar cells have attracted a large interested due to their large potential for efficiency enhancement. In plasmonic solar cells, metallic nanostructures with a plasmon resonance in the visible spectrum range are placed in contact with a solar cell, leading to an enhanced absorption. This effect is most pronounced if high efficiency third generation solar cells made of InAs quantum well structures embedded in a p-i-n GaAs are used. While the general principle for the enhanced absorption is quite clear, means for optimizing these structures to obtain highest efficiencies have to be taken. For instance, bandgap engineering may be used to match the quantum wells to the plasmons radition field. To address these issues, the coupling between plasmons in various nanostructures placed on or below InAs/GaAs solar cells will be investigated while a strong focus will be given to the fabrication of optimal solar cell structures.