Robust ultrahigh-Q resonances in tetramer metasurfaces through centroid symmetry protection and area conservation.

ABSTRACT: Ultrahigh-Q optical resonances are the cornerstone of next-generation nanophotonic technologies, but their simultaneous realization of robustness and on-chip practicality remains a significant challenge. In this work, we present tetramer composite metasurfaces capable of supporting two distinct classes of ultrahigh-Q resonances: centroid symmetry-protected bound states in the continuum (SP-BICs) and area-conserved guided-mode resonances (GMRs). By employing a four-hole supercell design, we demonstrate that centering each hole within its subcell preserves C_4v symmetry, thereby enabling SP-BICs. Controlled lateral displacement transforms them into quasi-BICs with Q > 10⁶. Independently, enforcing diagonal-hole area conservation within the super unit cell generates degenerate GMRs

SUBMITTER: Zhou C 

PROVIDER: S-EPMC12830976 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature