Plasmonic Light Trapping in Thin-Film Photovoltaics

Real nanophotovoltaic cells sometimes coat their thin absorber layer with metal nanoparticles a few tens of nanometres across. Driven near their localized surface plasmon resonance, these nanoparticles scatter incoming light sideways into the absorber instead of letting it pass straight through, lengthening the optical path and boosting absorption of otherwise weakly-absorbed long-wavelength photons. This simulation renders a 3D nanoparticle array on a thin absorber slab: tune the metal (Ag/Au/Cu), the host dielectric index, the incident wavelength and the nanoparticle size/coverage, and watch individual photons either scatter into the film near resonance or pass straight through off-resonance, while live readouts track the resonance wavelength, detuning, measured absorption and the resulting light-trapping enhancement factor versus a bare film.