Alternating Current Photovoltaic Effect Enhanced Heat‐Resisting GaN Photodetector and Its Application in Highly Sensitive Wind Speed Sensing

Gallium nitride (GaN)‐based ultraviolet (UV) photodetectors (PDs) are promising for advanced UV detection. However, the development faces challenges in cost reduction, process complexity, and the need for enhanced detection performance. In this study, an alternating current photovoltaic (AC PV) effect was identified in a GaN Schottky junction, achieving UV photoelectric responsivity improvements of up to two orders of magnitude and superior response speed compared to conventional photocurrent. Heating tests confirm PD stability at 600°C, attributable to the AC PV effect that maintains high response speed. Additionally, integrating a magnetically levitated structure with the UV PD enables a highly sensitive photoelectric wind speed sensor with an ultra‐low startup wind speed of 0.5 m/s and a rapid response time of 25.3 ms. This study offers a promising approach for fabricating high‐performance UV photoelectric devices and precise monitoring in challenging environments.