Bound states in the continuum in periodic structures with structural disorder

We study the effect of structural disorder on the transition from the bound states in the continuum (BICs) to quasi-BICs by the example of the periodic photonic structure composed of two layers of parallel dielectric rods. We uncover the specificity in the robustness of the symmetry protected and accidental BICs against various types of structural disorder. We analyze how the spatial mode localization induced by the structural disorder results in an effective reduction of the system length and limits the Q factor of quasi-BICs. Our results are essential for the practical implementation of BICs especially in natural and self-assembled photonic structures, where the structural disorder plays a crucial role.

Automated summary

This study investigates the impact of structural disorder on the transition from bound states in the continuum to quasi-BICs in periodic photonic structures. The robustness of symmetry protected and accidental BICs against various types of structural disorder is uncovered, with analysis revealing how spatial mode localization induced by disorder reduces system length and limits the Q factor of quasi-BICs. These findings are crucial for practical implementation of BICs, particularly in natural and self-assembled photonic structures where structural disorder plays a significant role.