Strong Broadband Terahertz Optical Activity through Control of the Blaschke Phase with Chiral Metasurfaces

Journal Article (Journal Article)

We demonstrate terahertz chiral metamaterials that achieve resonant transmission and strong optical activity. This response is realized in a metasurface coupled to its Babinet complement, with additional twist. Uniquely, the optical activity achieved in this type of metamaterial is weakly dispersive around the resonant transmission maxima, but it can be highly dispersive around the transmission minima. It has recently been shown that this unique optical activity response is closely related to zeros in the transmission spectra of circular polarizations through the Kramers-Kronig relations and strong resonant features in the optical activity spectrum corresponding to the Blaschke phase terms. Here we demonstrate how modifying the meta-atom geometry greatly affects the location and magnitude of these Blaschke phase terms. We study three different meta-atoms, which are variations on the simple cross structure. Their responses are measured using terahertz time-domain spectroscopy and analyzed via numerical simulations.

Full Text

Duke Authors

Cited Authors

  • Cole, MA; Chen, WC; Liu, M; Kruk, SS; Padilla, WJ; Shadrivov, IV; Powell, DA

Published Date

  • July 21, 2017

Published In

Volume / Issue

  • 8 / 1

Electronic International Standard Serial Number (EISSN)

  • 2331-7019

Digital Object Identifier (DOI)

  • 10.1103/PhysRevApplied.8.014019

Citation Source

  • Scopus