High transmission with narrow bandwidth of metallic defect mode in 1-D dielectric photonic crystals

摘要

Enhanced transmission peaks can be obtained in a dielectric photonic crystal with metal film defect. These peaks occur only in the band gaps, and their heights decrease sharply when they deviate from the band gaps. Theoretical analysis shows that, since the metal film defect mode possesses very high density of mode, high transmission of light in particular band can be achieved even by a metal "block" while high absorption of the light in other bands still exists. The physical mechanism of this phenomenon is essentially different from the resonant tunneling effect of layered metallic films. Since metal has high reflection and strong absorption of the light wave without being enhanced, so, basing on this mechanism, a narrow bandwidth filter with high transmission in UV range and suppression in while the visible, infrared, and even microwave range can be achieved.