Self-filtering monolithic organic/PbS quantum dot photodetector for visible and short-wave infrared selective vision in low-light

Dual-mode photodetectors with vertically stacked photoactive layers enable bias-controlled, band-selective extraction from their constituent photoactive layers. While their applications ranging from non-invasive diagnostics to optical communication demand high-fidelity detection of faint light, performance is often limited by interlayer-derived structural complexity and noise. Here, we present an interlayer-free monolithic organic/PbS photodetector that achieves visible and short-wave infrared dual-mode operation with low noise and crosstalk. Inducing vertical and lateral phase-separation in the organic layer facilitates charge carrier dynamics that yield high specific detectivity without auxiliary interlayers, enabling simple device structures that detect small signals with high precision. This strategy can be utilized in a variety of photoactive layer combinations spectrally targeted for application-specific devices. Its practicality is demonstrated through single-pixel imaging, which reconstructs high-fidelity images across visible and SWIR bands even under light attenuation. Furthermore, its dual-mode capability enables silicon alignment through registration of front- and back-side features. Dual-mode photodetectors can selectively detect light from stacked layers, but performance is limited by structural complexity and noise between layers. Oh et al. create an interlayer-free device that improves sensitivity and accuracy, enabling high-quality imaging under weak light.