Self-powered photodetectors capable of autonomous operation in real-world electromagnetic environments are essential for next-generation smart infrastructure monitoring. This work presents the theoretical design and numerical simulation of a flexible, transparent tri-layer graphene–InP Schottky photodetector for zero-bias operation, exploiting electromagnetic energy inductively harvested from high-voltage AC transmission lines. The device is analyzed within an electromagnetic–optical coupling framework, wherein the built-in electric field at the graphene–InP junction governs photogenerated carrier separation without external bias. Finite-element simulations reveal localized field enhancement ( η > 10) at the junction, promoting plasmon-assisted absorption and improving predicted responsivity. The simulated peak responsivity reaches 1.76 A/W at 1550 nm, attributed to a trap-mediated internal photogain mechanism, with an ultralow predicted dark current (~10⁻¹⁵ A) consistent with high-quality Schottky barrier formation. A 3-dB bandwidth of 2.5 GHz is predicted within the applicable gain-bandwidth regime. Broadband spectral response spanning 300–1700 nm enables simultaneous detection of corona-induced UV/visible emission and near-infrared thermal anomalies critical for grid monitoring. Fabricated on a flexible polyimide substrate, the device achieves predicted 85% optical transmittance and mechanical stability beyond 1000 bending cycles at a 5 mm radius. Detectivity is estimated at D ⁎ ≈ 1.2 × 10 ¹ ³ Jones at 1550 nm under zero-bias conditions. All metrics are simulation-based predictions serving as theoretical targets for subsequent experimental validation, positioning graphene–InP Schottky junctions as a compelling platform for electromagnetic and photonic sensing in advanced smart grid systems.
Arash Vaghef-Koodehi (2026) studied this question.