Observation of zero-transmission dip in a single-layer electric metamaterial with finite non-radiative loss

Abstract

We propose a theory for realizing a zero-transmission dip in the transmission spectrum of a reflectionless single-layer metamaterial designed based on the Brewster effect by variably controlling the radiative loss of the metamaterial in response to the non-radiative loss. The radiative loss can be controlled while maintaining broadband zero reflection by varying the relationship between the orientation of the constituent meta-atoms and the incident electromagnetic fields. As a verification of the proposed theory, we design a reflectionless metamaterial by arranging meta-atoms that exhibit a simple electric dipole resonance in a two-dimensional lattice. The numerically calculated and experimentally measured transmission spectra of this metamaterial demonstrate that the radiative loss can be controlled by changing the arrangement of the meta-atoms without altering their structure, and that a zero-transmission dip can be observed for a certain arrangement of the meta-atoms. This study could lead to the development of material sensing, especially for lossy materials based on resonant metamaterials.