Thickness Dependence of Plasmonic Charge Carrier Generation in Ultrathin a-Si:H Layers for Solar Cells
Journal article, 2011

Nanocomposite layers of Ag nanoparticles and a-Si:H film constitute attractive candidates for the realization of ultrathin "two- dimensional" plasmonic solar cells, with an ideal 18% efficiency predicted for an average layer thickness of only 20 nm. By combining optical spectroscopy with photoconductivity measurements, we here characterize different contributions to the light absorption and charge carrier generation in such nanocomposites. We focus in particular on the important role of the absorber layer thickness for these processes, by studying a range of a-Si:H thicknesses from 9 to 67 nm. Through detailed comparison with numerical calculations by the finite element method, observed experimental features are connected to specific resonance modes and charge carrier generation mechanisms. The influence of dipolar and quadrupolar near-field distributions are evaluated with respect to different figures of merit for plasmonic solar cells. We briefly discuss how the present findings may be implemented in practical solar cell configurations. © 2011 American Chemical Society.

figure of merit

Ultrathin plasmonic solar cells

nanocomposites

2D photovoltaics

amorphous hydrogenated silicon

Author

Viktoria Gusak

Chalmers, Applied Physics, Chemical Physics

Bengt Herbert Kasemo

Chalmers, Applied Physics, Chemical Physics

Carl Hägglund

Chalmers, Applied Physics, Chemical Physics

ACS Nano

1936-0851 (ISSN) 1936-086X (eISSN)

Vol. 5 8 6218-6225

Areas of Advance

Nanoscience and Nanotechnology

Subject Categories

Atom and Molecular Physics and Optics

Condensed Matter Physics

DOI

10.1021/nn201074z