High-Performance Broadband (300-1600 nm) Si-Based Photodetector Enabled by 2.5D Out-of-Plane Architecture Metasurface Enhancement

Bound states in the continuum (BIC) are highly effective at confining electromagnetic waves, significantly enhancing light-matter interactions. Here, we propose unique plasmonic bound states in the continuum metasurface based on 2.5D metal/Si nanocone arrays with out-of-plane architectures, achieving broadband (300–1600 nm) absorption capabilities. At 1550 nm, the absorption of our device is nearly 100%. Under ultraviolet to visible light irradiation, our detector demonstrates an external quantum efficiency close to unity.