Robust chirality via merging accidental BICs with net zero topological charge

Abstract Chiral metasurfaces leveraging bound states in the continuum (BICs) offer a powerful route for enhancing light–matter interactions. However, existing quasi-BIC architectures typically face a fundamental trade-off between high quality (Q) factors and wide-angle chiral operation. Most designs confine strong circular dichroism (CD) to isolated points in momentum space (k-space) and often rely on intricate three-dimensional (3D) meta-atoms, rendering them highly sensitive to fabrication imp