Glass-loaded asymmetric surface plasmon polariton spread device of SiO2-gold film-SiO2 waveguide structure

Abstract

The invention discloses a glass-loaded asymmetric surface plasmon polariton spread device of a SiO2-gold film-SiO2 waveguide structure. The device is characterized by comprising a top SiO2 layer, a gold film layer, an L-shaped glass layer and a bottom SiO2 layer which are sequentially laminated, wherein the outer end face of the L-shaped long edge of the glass layer is laminated with the gold film layer; the inner end face of the L-shaped long edge is laminated with the bottom SiO2 layer; a grating structure is etched on the gold film layer; spread conduction type SPPs produced on the interface of the top SiO2 layer-gold film layer through excitation is enhanced by the grating structure. According to the device, the SPPs is excited by using the similar Kretschmann structure; the SPPs excitation is enhanced by using the grating structure; localization in the SPPs spread process is enhanced between glass and the SiO2 layer by total reflection by using reflected light of the gold film; the SPPs spread distance is meanwhile improved without sacrificing the sub-wavelength confinement of the waveguide. Key devices can be provided for application of the SPPs in the aspects such as novel photonic devices, wideband communication systems, tiny photonic circuits and optoelectronic integration; the device is low in cost and easy to implement.

Description

technical field [0001] The invention relates to optical communication technology, in particular to a glass-loaded asymmetric SiO 2 -Gold film-SiO 2 Surface plasmon propagation device with waveguide structure. Background technique [0002] Surface plasmon polaritons (SPPs for short) is an electromagnetic mode between a light wave and a migratable surface charge realized by changing the subwavelength structure of the metal surface, which can support the surface plasmon wave transmitted at the interface between the metal and the medium. Light energy is thus transmitted without being limited by the diffraction limit. Because of the unique properties of SPPs, it plays an important role in manipulating light energy at the nanoscale. Especially in the low temperature environment designed by Professor Oulton of Imperial College London, the covering thin MgF 2 The CdS nanowire structure is added to the silver film, and the experimental device is made of 15nm SiO 2 The ball is wr...

AI Technical Summary

Problems solved by technology

However, although the researchers have achieved the confinement of the optical field to the order of tens of nanometers, the loss of the designed waveguide device is still very large

The main difficulty faced in the application of SPPs technology at present is that due to the strong attenuation caused by the Ohm effect, the transmission distance of 500nm visible light in an ideal single interface (the length when the oscillation intensity is reduced to 1 / e) is about 1.8 μm

This obviously cannot realize the application of photonic devices, and realizing loss-compensation in SPPs propagation is still the primary goal of transforming SPPs photonic devices into practical ones.

[0004] Through search and novelty search, it is found that gain media are mostly used to compensate for SPPs attenuation, but this sacrifices the advantages of waveguide sub-wavelength scale and localization of electric field strength.

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