Nanosecond-Response Speed Sensor Based on Perovskite Single Crystal Photodetector Array

A nanosecond-response speed sensor is demonstrated based on a CH₃NH₃PbI₃ perovskite single crystal photodetector array. The responsivity of the CH₃NH₃PbI₃ photodetector unit is as high as 1.55 × 10² A/W under 1.93 × 10^-2 mW/cm² illumination with a 532 nm laser. The ultrafast response time of less than 12.5 ns makes it possible for ultra-high-speed detection. Owing to the uniformity of as-prepared CH₃NH₃PbI₃ single crystals, each array element shows a consistent performance. When a shelter moves across the photodetector array, the time delay of the photoresponses between two neighboring array elements can be recorded promptly. Therefore, the speed of the moving shelter can be calculated easily. Besides speed sensing, the ability to capture the trajectory of a moving object is also demonstrated. The nanosecond-response speed sensor presented here demonstrates great potential for applying in high-speed detection.