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Optical activity enhanced by strong inter-molecular coupling in planar chiral metamaterials.

ABSTRACT: The polarization of light can be rotated in materials with an absence of molecular or structural mirror symmetry. While this rotating ability is normally rather weak in naturally occurring chiral materials, artificial chiral metamaterials have demonstrated extraordinary rotational ability by engineering intra-molecular couplings. However, while in general, chiral metamaterials can exhibit strong rotatory power at or around resonances, they convert linearly polarized waves into elliptically polarized ones. Here, we demonstrate that strong inter-molecular coupling through a small gap between adjacent chiral metamolecules can lead to a broadband enhanced rotating ability with pure rotation of linearly polarized electromagnetic waves. Strong inter-molecular coupling leads to nearly identical behaviour in magnitude, but engenders substantial difference in phase between transmitted left and right-handed waves.

SUBMITTER: Kim TT

PROVIDER: S-EPMC4160707 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Optical activity enhanced by strong inter-molecular coupling in planar chiral metamaterials.

Kim Teun-Teun TT Oh Sang Soon SS Park Hyun-Sung HS Zhao Rongkuo R Kim Seong-Han SH Choi Wonjune W Min Bumki B Hess Ortwin O

Scientific reports 20140911

The polarization of light can be rotated in materials with an absence of molecular or structural mirror symmetry. While this rotating ability is normally rather weak in naturally occurring chiral materials, artificial chiral metamaterials have demonstrated extraordinary rotational ability by engineering intra-molecular couplings. However, while in general, chiral metamaterials can exhibit strong rotatory power at or around resonances, they convert linearly polarized waves into elliptically polar ...[more]

PMID: 25209452

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