title: Theoretical Study of Light Trapping in Nanostructured Thin Film Solar Cells Using Wavelength-Scale Silver Particles.
abstract: We propose and theoretically evaluate a plasmonic light trapping solution for thin film photovoltaic devices that comprises a monolayer or a submonolayer of wavelength-scale silver particles. We systematically study the effect of silver particle size using full-wave electromagnetic simulations. We find that light trapping is significantly enhanced when wavelength-scale silver particles rather than the ones with subwavelength dimensions are used. We demonstrate that a densely packed monolayer of spherical 700 nm silver particles enhances integrated optical absorption under standard air mass 1.5 global (AM1.5G) in a 7 μm-thick N719-sensitized solar cell by 40% whereas enhancement is smaller than 2% when 100 nm ones are used. Superior performance of wavelength-scale silver particles is attributed to high-order whispering gallery modes that they support. These modes scatter the light over a wider angular range, hence increasing the density of both waveguide and resonance modes within the dye-sensitized layer.
authors.affiliation: †Photovoltaics and Thin Film Electronics Laboratory, Ecole Polytechique Fédérale de Lausanne (EPFL), Rue de la Maladière 71, Neuchatel 2000, Switzerland.|‡Department of Physics, Sharif University of Technology, Tehran 14588, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Dabirian
authors.affiliation: ‡Department of Physics, Sharif University of Technology, Tehran 14588, Iran.
authors.forename: Nima
authors.initials: N
authors.lastname: Taghavinia
keywords: dye-sensitized solar cell; light scattering; light trapping; plasmonic; thin film solar cell