Terahertz In‐Sensor Computing Utilizing Photothermoelectric Thin Films

Abstract Terahertz (THz) detection is pivotal for biomedical diagnostics and security screening, enabled by its non‐ionizing nature and characteristic “fingerprint” spectra. However, weak THz–matter interactions, energy‐intensive processing, and complex hardware integration hinder its practical use. To this aim, a layered bismuth selenide (Bi 2 Se 3 )‐based THz detection array is fabricated via low‐temperature pulse irradiation synthesis (PIS), exhibiting a tunable thermally coupled bidirectional response. The intrinsic photothermoelectric (PTE) effect enables adaptive in‐sensor THz signal processing, achieving 200 V W −1 responsivity and <5 ms response time at 0.3 THz in a self‐powered mode. Integrated in‐sensor computing enhances accuracy through real‐time noise suppression, edge detection, and feature extraction. The array also demonstrates high imaging performance, with a >90% recall rate for concealed object detection. This work provides a scalable, high‐precision THz sensing platform with transformative potential for biomedical and security applications.