Supplement 1: K-space design of terahertz plasmonic filters

Originally published in Optica on 20 March 2015 (optica-2-3-214

Resonantly-enhanced transmission through a periodic array of subwavelength apertures in heavily-doped conducting polymer films

We observed resonantly-enhanced terahertz transmission through two-dimensional (2D) periodic arrays of subwavelength apertures with various periodicities fabricated on metallic organic conducting polymer films of polypyrrole heavily doped with PF6 molecules [PPy(PF6)]. The "anomalous transmission" spectra are in good agreement with a model involving surface plasmon polariton excitations on the film surfaces. We also found that the 'anomalous transmission' peaks are broader in the exotic metallic PPy(PF6) films compared to those formed in 2D aperture array in regular metallic films such as silver, showing that the surface plasmon polaritons on the PPy(PF6) film surfaces have higher attenuation