Spaceplates have emerged in the context of nonlocal metasurfaces, enabling the
compression of optical systems by minimizing the required empty space between their …

Due to the exceptional light confinement capabilities, optical bound states in the continuum
(BICs) have attracted a lot of interest in both fundamental and applied research. It has …

In this work, we develop a perturbation theory to analyze resonant states near a bound state
in the continuum (BIC) in photonic crystal slabs. The theory allows us to rigorously determine …

Bound states in the continuum (BICs) in planar photonic structures have attracted broad
scientific interest owing to their exceptional capability to confine light. Topological …