Key points are not available for this paper at this time.
Plasmonic hot-electron-based photodetectors (HEB-PDs) have received widespread attention for their ability to realize effective carrier collection under sub-bandgap illumination. However, due to the low hot electron emission probability, most of the existing HEB-PDs exhibit poor responsivity, which significantly restricts their practical applications. Here, by employing the binary-pore anodic alumina oxide template technique, we proposed a compact plasmonic bound state in continuum metasurface–semiconductor–metal-based (BIC M–S–M) HEB-PD. The symmetry-protected BIC can manipulate a strong gap surface plasmon in the stacked M–S–M structure, which effectively enhances light–matter interactions and improves the photoresponse of the integrated device. Notably, the optimal M–S–M HEB-PD with near-unit absorption (∼90%) around 800 nm delivers a responsivity of 5.18 A/W and an IPCE of 824.23% under 780 nm normal incidence (1 V external bias). Moreover, the ultrathin feature of BIC M–S–M (∼150 nm) on the flexible substrate demonstrates excellent stability under a wide range of illumination angles from −40° to 40° and at the curvature surface from 0.05 to 0.13 mm–1. The proposed plasmonic BIC strategy is very promising for many other hot-electron-related fields, such as photocatalysis, biosensing, imaging, and so on.
Wang et al. (Fri,) studied this question.