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Updated: May 16, 2026

Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
Collimation effect inside complete bandgap of electromagnetic surface resonance states on a metal plate perforated
Yang Cao1, Zeyong Wei, Chao Wu
1Department of Physics, Tongji University, Shanghai, 200092, China.
Abstract:
In this paper the transmission properties of a metal plate perforated with a triangular array of air holes is investigated. We find that the normalized transmittivity exceeds unity within a certain frequency range under normal incidence of a Gaussian beam. Calculations and experiments indicate that the phenomenon results from the collimation effect which only occurs inside the complete bandgap of surface resonance states on the perforated metal plate. The findings present a simple approach for beam collimation.
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