Exceptional Bound States in the Continuum

• DOI: 10.48550/arxiv.2309.01501
• Publication Date: 2023-01-01
• Authors: Adrià Canós Valero; Zoltan Sztranyovszky; E. A. Muljarov; Andrey Bogdanov; Thomas Weiß
• Keywords: Condensed Matter - Materials Science; Condensed Matter - Mesoscale and Nanoscale Physics; Mesoscale and Nanoscale Physics (cond-mat.mes-hall); Materials Science (cond-mat.mtrl-sci); FOS: Physical sciences; Physics - Optics; Optics (physics.optics)

Bound states in the continuum (BICs) and exceptional points (EPs) are unique singularities of non-Hermitian systems. BICs demonstrate enhancement electromagnetic field at nanoscale, while EPs exhibit high sensitivity to small perturbations. Here, we that several can be merged into one EP, forming an EP-BIC. The resulting state inherits properties from both namely, it does not radiate shows extremely We validate developed theory with numerical simulations formation second third-order EP-BICs stacked dielectric metasurfaces. also show losses leaky resonances anomalous behavior when unit cell is broken, which differs asymptotics commonly attributed BICs.