Influence of center fractal patterns on the transmission spectrum and electric field intensity enhancement in gold/glass plasmonic nanostructures

• Intensity enhancement factor becomes larger with increasing order of fractal.
• Incident wave is confined in the center of the basic unit.
• There are more transmission peaks in our structure compared with a planar gold film.

In this work, a type of fractal nanostructure (center fractal) based on Au film/glass substrate metal/dielectric system was investigated. The effects of various structural parameters (edge length, period and fractal order) on the optical response of the nanostructures were studied by the Rigorous Coupled Wave Analysis (RCWA) method. The electric field intensity enhancement factor of the fractal patterns becomes larger with increasing order of the fractal pattern nanostructure. Resonant wavelength peaks (transmission peaks) were observed in the fractal nanostructures. Moreover, under the same periodicity and order, the resonant wavelengths increase linearly with the sizes of the basic unit. The nanostructure can improve the electric field intensity enhancement and transmission properties.

Figure optionsDownload as PowerPoint slide