Triple-Periodical Photonic Crystal Heterostructures for Multichannel Ultranarrow Transmission Filters

Triple-periodical photonic crystal heterostructures (ABC)^N for multichannel ultranarrow transmission filters are designed and demonstrated. Theoretical calculations and experimental results from TiO₂/SiO₂ constructed heterostructures show that each transmission channel can reach subnanometre scale, implying technical importance of such structures in the fields of integrated optics, optical communications for the design of high-performance multichannel filters, wavelength division multiplexing (WDM) and dense wavelength division multiplexing (DWDM) systems, etc.