Open AccessBroadband plasmon-induced transparency in terahertz metamaterials via constructive interference of electric and magnetic couplings
Author(s) -
Mingli Wan,
Yunfei Song,
Liufang Zhang,
Fengqun Zhou
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.027361
Subject(s) - metamaterial , terahertz radiation , split ring resonator , resonator , optics , electromagnetically induced transparency , plasmon , magnetic dipole , electric field , optoelectronics , fano resonance , slow light , materials science , photonic metamaterial , dipole , physics , photonic crystal , quantum mechanics
Plasmon-induced transparency (PIT) is a result of destructive interference of different plasmonic resonators. Due to the extreme dispersion within the narrow transparency window, PIT metamaterials are utilized to realize slow light and nonlinear effect. However, other applications such as broadband filtering more desire a broad transmission frequency band at the PIT resonance. In this paper, a broadband PIT effect is demonstrated theoretically in a planar terahertz metamaterial, consisting of a U-shaped ring (USR) supporting electric and magnetic dipole modes as the bright resonator and a cut wire pair (CWP) possessing planar electric quadrupole and magnetic dipole modes as the dark resonator. The dark resonant modes of the CWP can be excited simultaneously via near-field by both the electric and magnetic dipole modes of the USR. When the electric as well as magnetic excitation pathways constructively interact with each other, the enhanced near-field coupling between bright and dark resonators gives rise to an ultra-broad transparency window across a frequency range greater than 0.61 THz in the transmittance spectrum.