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arXiv · 1604.05244

Large Enhancement of Circular Dichroism Using an Embossed Chiral Metamaterial

S. Hamed Shams Mousavi·Sajanlal R. Panikkanvalappil·Mostafa A. El-Sayed·Ali A. Eftekhar·Ali Adibi
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Abstract

In the close vicinity of a chiral nanostructure, the circular dichroism of a biomolecule could be greatly enhanced, due to the interaction with the local superchiral fields. Modest enhancement of optical activity using a planar metamaterial, with some chiral properties, and achiral nanoparticles has been previously reported. A more substantial chirality enhancement can be achieved in the local filed of a chiral nanostructure with a three-dimensional arrangement. Using an embossed chiral nanostructure designed for chiroptical sensing, we measure the circular dichroism spectra of two biomolecules, Chlorophylls A and B, at the molecular level, using a simple polarization resolved reflection measurement. This experiment is the first realization of the on-resonance surface-enhanced circular dichroism, achieved by matching the chiral resonances of a strongly chiral metamaterial with that of a chiral molecule, resulting in an unprecedentedly large differential CD spectrum from a monolayer of a chiral material.

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S. Hamed Shams Mousavi, Sajanlal R. Panikkanvalappil, Mostafa A. El-Sayed, Ali A. Eftekhar, Ali Adibi. 2016-04-18. Large Enhancement of Circular Dichroism Using an Embossed Chiral Metamaterial. https://arxiv.org/abs/1604.05244

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