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arXiv · 1704.08374

Complete photonic bandgaps in supercell photonic crystals

Alexander Cerjan·Shanhui Fan
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Abstract

We develop a class of supercell photonic crystals supporting complete photonic bandgaps based on breaking spatial symmetries of the underlying primitive photonic crystal. One member of this class based on a two-dimensional honeycomb structure supports a complete bandgap for an index-contrast ratio as low as $n_{high}/n_{low} = 2.1$, making this the first such 2D photonic crystal to support a complete bandgap in lossless materials at visible frequencies. The complete bandgaps found in such supercell photonic crystals do not necessarily monotonically increase as the index-contrast in the system is increased, disproving a long-held conjecture of complete bandgaps in photonic crystals.

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Alexander Cerjan, Shanhui Fan. 2017-04-26. Complete photonic bandgaps in supercell photonic crystals. https://doi.org/10.1103/physreva.96.051802

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