A slot-waveguide is an optical waveguide that guides strongly confined light in a subwavelength-scale low refractive index region by total internal reflection.
A slot-waveguide consists of two strips or slabs of high-refractive-index (nH) materials separated by a subwavelength-scale low-refractive-index (nS) slot region and surrounded by low-refractive-index (nC) cladding materials.
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