Optical guided waves at graded metal-dielectric interfaces.
نویسندگان
چکیده
Waveguides at interfaces with a linearly graded permittivity between a metal and a dielectric are studied. Analytic expressions for the dispersion relations, modes, losses, and cutoff wavelengths are derived and agree well with simulations. The gradation results in anomalous dispersion, a reduction in the energy velocity, and increased field confinement in the metal-dielectric transition region. These effects lead to increased propagation losses, which are sensitive to the spatial extent of the interface gradation.
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عنوان ژورنال:
- Optics letters
دوره 36 11 شماره
صفحات -
تاریخ انتشار 2011