Hot electron-generated plasmon resonance in ultrathin solar absorbers: Experiment

We describe experimental progress on a hot electron PV structure based on hot electron plasmon protection (HELPP) [1] that provides a path to solar efficiency in excess of the Shockley-Queisser limit. It combines hot electron recovery in ultrathin junctions with superabsorption in metamaterial/plasmonic nanosystems and a HELPP/ plasmon resonance energy transfer (PRET) mechanism. Measurements of optical absorbance (via reflectance and transmittance) of Ag nanopatterns on p- and n-type crystalline and amorphous Si absorbers were performed at incident wavelengths from 350 to 2,500 nm. In samples prepared with Ag nanopatterns with dimensions tuned to provide a resonance near 1,600 nm, we indeed observed such a resonance. We discuss these and other experimental results associated with hot electron-facilitated plasmon resonances.\\[4pt] [1] K. Kempa, ``Plasmonic protection of the hot-electron energy,'' Phys. Stat. Sol. RRL, \textbf{7}, 465-468 (2013).