Multifunctional metasurfaces empowered by bound states in the continuum

Hu, Haiyang (2025): Multifunctional metasurfaces empowered by bound states in the continuum. Dissertation, LMU München: Faculty of Physics

Abstract

Metasurfaces, consisting of two-dimensional arrays of nanostructures, have significantly advanced photonics by enabling precise control over light-matter interactions in compact designs. Bound states in the continuum (BICs) have garnered increasing attention as a key mechanism underpinning recent performance advances of metasurfaces, offering spectral selectivity, strong light confinement, and significant enhancement of electromagnetic fields. This thesis explores BIC metasurfaces as a versatile platform across diverse domains, bridging fundamental principles with practical applications. The foundational chapters provide a theoretical framework for understanding BICs, including their symmetry-driven confinement mechanisms and topological properties, and outline advanced methodologies for their design, fabrication, and optical characterization. Building on this foundation, the application-focused chapters demonstrate the transformative potential of BIC metasurfaces. In photocatalysis, BIC metasurfaces enhance light absorption and energy localization, significantly improving catalytic efficiency. For surface-enhanced Raman spectroscopy (SERS), they provide a tunable, reproducible alternative to conventional plasmonic platforms, enabling high-sensitivity molecular detection. In dynamic electrical tunability, reconfigurable BIC metasurfaces offer unprecedented control over optical responses, unlocking new possibilities in adaptive optics and sensing technologies. The multidisciplinary research presented in this thesis presented the potential of BIC-driven metasurfaces as multifunctional photonic devices, integrating energy conversion, sensing, and reconfigurable functionalities.

• Item Type: Theses (Dissertation, LMU Munich)
• Keywords: metasurfaces, BIC, Raman, tuning
• Subjects: 500 Natural sciences and mathematics; 500 Natural sciences and mathematics > 530 Physics
• Faculties: Faculty of Physics
• Language: English
• Date of oral examination: 24. April 2025
• 1. Referee: Tittl, Andreas
• Signature of the printed copy: 0001/UMC 31208