Gate-Switchable Nonlinear Photoresponse in a Dangling-Bond-Free Nanowire Photodetector.

As intelligent optoelectronic systems advance, photodetectors with switchable nonlinear responses are increasingly desirable. However, conventional materials exhibit only sublinear behavior, and superlinear strategies rely on heterojunctions lacking reversible modulation. Here, we report one-dimensional Ta2Pd3Se8 nanowires obtained by electrochemical intercalation and exfoliation. Their dangling-bond-free chain architecture suppresses carrier scattering and photogenerated recombination, yielding an electron mobility of 38.95 cm2 V-1 s-1, a responsivity of 58.14 A/W, a photoconductive gain of 137.1, and a specific detectivity of 1.48 × 1011 Jones. Notably, tuning the gate voltage continuously switches the power exponent α from 1.74 to 0.50, corresponding to a 248% modulation range, surpassing all back-gated low-dimensional visible photodetectors. This switching arises from gate-modulated trap-state occupation. Furthermore, the gate-tunable nonlinear photoresponse enables adaptive image convolution, including salient-feature enhancement, high-fidelity convolution, and dynamic-range compression. Our work establishes the nanowires as a platform for tunable photodetectors for autonomous driving, unmanned aerial vehicles, and intelligent defense systems.