Enlargement of nontransmission frequency range in photonic crystals by using multiple heterostructures

We show theoretically that the nontransmission frequency range of photonic crystals can be substantially enlarged as desired by using multiple heteros tructures. This photonic multiple heterostructure consists of different pho tonic crystals. The constituent photonic crystals are chosen such that the nontransmission frequency ranges of the adjacent constituents are arranged in a way similar to the type-II lineup of the band-gaps in semiconductor he terostructures. Examples in the two-dimensional systems are demonstrated th eoretically by using transfer matrix methods. (C) 2000 American Institute o f Physics. [S0021-8979(00)00105-5].