Bio-inspired hierarchical plasmonic meta-architectures for silicon-based near-infrared sensing

Hierarchical photonic architectures in nature, exemplified by peacock feathers, encode rich optical functionalities through nested structures spanning multiple length scales. By contrast, metasurfaces are typically built on single-level, planar designs, where one-scale optimization constrains three-dimensional control of light concentration and near-field localization. Here, we report a bio-inspired hierarchical plasmonic hot-carrier infrared detector in which microscale resonant motifs are integrated with embedded subwavelength features to realize multiscale field shaping at the device level. By co-designing the hierarchical metastructure directly with a TiN/Si Schottky junction, the metasurface functions as an in-device light-harvesting and field-engineering element, avoiding reliance on external optical add-ons and offering a practical route toward more compact architectures. The hierarchical geometry delivers a pronounced performance gain and serves as a multiscale tuning knob that programmably reshapes the near-field landscape and modulates device response by design. As a result, the device exhibits enhanced infrared absorption and improved hot-carrier collection, achieving a responsivity of 56 mA/W and a detectivity of 3.42×1010 Jones at 1200 nm under room-temperature, zero-bias operation. Our results establish hierarchical plasmonic meta-architectures as a structure-driven strategy for high-performance hot-carrier infrared (IR) detection and underscore their potential for metasurface-detector co-design toward wafer-scale metasurface-detector co-integration for next-generation, full-field infrared detection.