Gate‐Programmable Broadband Photodetector for In‐Sensor Computing and Encryption

ABSTRACT Next‐generation intelligent perception systems require photodetectors that are functionally reconfigurable for in‐sensor processing. However, integrating broadband response, polarization sensitivity, and electrically reconfigurable photoresponse into a single compact device remains challenging. Here, we demonstrate a solution using a gate‐programmable photodetector based on a 2H‐MoTe ₂ /ReSe ₂ heterojunction. The device exhibits self‐powered broadband detection from 300 to 900 nm, with a responsivity of 0.945 A/W, a specific detectivity of 1.41 × 10 ¹² Jones, and a polarization ratio of 16.45 at 635 nm. Critically, gate voltage asymmetrically modulates the dual built‐in fields via Fermi‐level tuning, enabling continuous and programmatic reconfiguration of the magnitude and polarity of photocurrent. The responsivity is tuned from 0.142 to −1.254 A/W, and this polarity reversal allows the polarization ratio range to span both positive and negative domains. Leveraging this unique programmability, we realize two advanced applications: multimodal encryption communication, where gate voltage and polarization angle serve as dual dynamic encryption keys, and in‐sensor image convolution for direct edge extraction at the sensor level. This work establishes a robust platform toward multifunctional and reconfigurable optoelectronics, advancing the development of all‐in‐one intelligent perception.