Photonics Applications in Third Generation Photovoltaics.

Micron-scale photonic devices and nanometer-scale materials science have considerably advanced the performance and functionality of silicon-compatible, planar photonics, in the last fifteen years. To date, the emphasis and impact of these studies and innovation have been focused on applications in optical communications, for enhancing fiber optic-based bandwidth and integrated circuit computation capacity. Recently, a renewed attention on improving alternative energy sources has inspired novel solutions to increasing Third Generation photovoltaic (PV) performance. This talk will review recent photonics results involving (i) photonic crystals and (ii) silicon nanocrystals, that in turn offer two unique approaches to enhance the external efficiency of silicon-based PV. (i) Results from a one-dimensional photonic crystal for selective guiding and routing of a VCSEL light source on an opto-electronic transceiver will be presented; the application of a two-dimensional photonic crystal for coupling normal incidence sunlight into the plane of a PV (by means of a Fano resonance) will be discussed. (ii) Results from the discovery of silicon nanocrystals in silicon nitride, and their role as optical sensitizers for Erbium excitation will be presented; the application of nanocrystals as scintillators and tandem cell layers for increasing Si PV responsivity will be discussed.