A self-powered Ga2O3/MgO/GaN heterojunction polarization-sensitive, superlinear, and solar-blind selectivity detector enabling optical neural networks

Solar-blind ultraviolet polarization detection is crucial for emerging photonic technologies, yet integrating solar-blind selectivity, ultrahigh polarization sensitivity, and self-powering operation in low-dimensional wide bandgap semiconductors remains challenging. Herein, we exhibit a highly polarization-sensitive, solar-blind selective and self-powered photodetector based on a one-dimensional Ga 2 O 3 single-crystals Van der Waals heterojunction (vdWh), in which Ga 2 O 3 single-crystals exhibit significant in-plane anisotropy with high electrical and optoelectrical anisotropies. Benefiting from interface engineering and a graphene transparent electrode, the detector exhibits superior performance with a responsivity of 0.20 A/W, a detectivity of 2.95×10 11 Jones, fast response times of 26.5/25.7 μs (rise/decay), and a record polarization sensitivity of 122 at 0 V. Critically, the detector exhibits a remarkable superlinear photoresponse, maintaining excellent performance under strong illumination, which is determined by space-charge trapping effect. Further, a photonic system combining a 10×10 photodetector array with polarization-resolved inputs achieves >88% trimodal classification accuracy and delivers 7 dB image enhancement under extreme noise, demonstrating critical advantages for intelligent vision in low-visibility environments. Beyond establishing a robust framework for advancing compact polarization photodetectors, this research facilitates the development of next-generation ultraviolet optoelectronics devices with novel functionalities specifically designed for harsh environments. This work presents a self-powered solar-blind photodetector based on an interface-engineered Ga 2 O 3 /MgO/GaN van der Waals heterojunction. It simultaneously achieves ultra-narrowband spectral selectivity, superlinear photoresponse, and high polarization sensitivity (polarization ratio >122 @260 nm). These advancements arise from engineered interfacial carrier transport and anisotropic crystal orientation, opening pathways for intelligent information recognition. • One-dimensional Ga 2 O 3 single crystals with strong in-plane anisotropy, solar-blind response, and high stability are synthesized via CVD. • The Ga 2 O 3 /MgO/GaN self-powered detector shows stable, spectrum-selective solar-blind UV detection with superlinear photoresponse under strong illumination. • The detector exhibits excellent polarization-sensitive response with a polarization ratio up to 122. • Leveraging the ultrahigh dichroic ratio and photoresponse, the detector in an optical neural network enables high-quality imaging even under noisy conditions.