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arXiv · 1006.1589

The Photonic Band theory and the negative refraction experiment of metallic helix metamaterials

Chao Wu·Hongqiang Li·Zeyong Wei·Xiaotong Yu·C. T. Chan
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Abstract

We develop a theory to compute and interpret the photonic band structure of a periodic array of metallic helices for the first time. Interesting features of band structure include the ingenuous longitudinal and circularly polarized eigenmodes, the wide polarization gap [Science 325, 1513 (2009)], and the helical symmetry guarantees the existence of negative group velocity bands at both sides of the polarization gap and band crossings pinned at the zone boundary with fixed frequencies. A direct proof of negative refraction via a chiral route [Science 306, 1353 (2004)] is achieved for the first time by measuring Gooshanchen shift through a slab of three dimensional bona fide helix metamaterial.

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Chao Wu, Hongqiang Li, Zeyong Wei, Xiaotong Yu, C. T. Chan. 2010-06-14. The Photonic Band theory and the negative refraction experiment of metallic helix metamaterials. https://doi.org/10.1103/physrevlett.105.247401

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