The hour-glass type nanostructures are fabricated by using the conventional Si processes. When beaming though these structures, we observed that light is collected by the micro scale pyramidal cavity, funneled through the nano-aperture by plasmonic resonance and collimated with enhanced transmission by the surrounding horn-like mirrors (optical horn-effect). Optical transmissions through pyramidal probes with various nano-aperture diameters were measured to be dependent upon the aperture area. For a diameter less than ~ 50 nm or less than area with ~10,000 nm2, the transmitted optical intensities are increasing due to the spp-mediated intra-band emission. For the aperture diameter greater than 100 nm, the strong spp-coupled emission is shown. In addition, for the Au (7×7) slit aperture array platform with the slit aperture for a ~ 10 nm width, the broad emission spectra ranging from 600 nm to 860 nm are observed possibly due to nearfield coupling with localized surface plasmon polariton (LSPP).
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