Distributed-Bragg-Reflection Assisted Tailoring of Extraordinary Transmission Spectrum in Sub-Wavelength Hole Array

We present a novel route to tailor the spectral features of extraordinary transmission (EOT) through sub-wavelength periodic hole array using a distributed-Bragg-reflector (DBR). The photonic stop-bands and high transmission regions in the DBR spectrum results in the creation of new EOT peaks in those spectral regions where conventional EOT spectrum exhibits negligible transmission. Modal-analysis for the composite geometry elucidates that the existence of such unconventional EOT peaks are reinforced by the transmission resonances of DBR. Also, by creating suitable defect states in the DBR transmission spectrum, we show that the bandwidth of conventional EOT peaks could be tailored significantly and narrowed down to less than 0.1-nm linewidth.