Higher order BIC of metasurface excited by magnetic EIT

Metasurfaces enable complex modulation of terahertz waves. However, the quality factor of metallic metasurfaces is often limited by intrinsic ohmic losses. The concept of bound states in the continuum (BIC) has been proposed to enhance terahertz-matter interactions. High order BICs have garnered attention due to their robustness. Previous studies on high-order BICs focused on photonic crystals, requiring high structural symmetry. In this paper, we propose a metasurface design based on the magnetic Electromagnetic induced transparency (EIT) effect to excite higher-order BIC eigenmodes. This novel approach and the resulting robust modes hold great potential for terahertz sensing and communication applications.