Light trapping in guided modes of thin-film silicon-on-silver waveguides by scattering from a nanostrip

摘要: Light trapping in a waveguide configuration consisting of thin planar film hydrogenated amorphous silicon (aSi:H) on silver backreflector is studied theoretically and experimentally. achieved by scattering light from or nanostrip placed directly the silicon-film surface. For films it appropriate to think terms coupling into guided modes air-aSi:H-silver configuration, which focus this paper. Using Green’s function surface integral equation method we calculate cross sections governing extinction, out-of-plane scattering, modes. It found for geometries with aSi:H-film thicknesses range 50–500 nm that distinct peaks extinction cross-section spectra are located at wavelengths determined cutoff modes, those insensitive precise geometry scatterer. Measurements an array strips spaced large distance 10 μm 290 nm be good agreement theoretical predictions.