Revolutionizing X‑ray Imaging: A Leap toward\nUltra-Low-Dose Detection with a Cascade-Engineered Approach

X-ray detection technology\nis essential in various fields, including\nmedical imaging and security checks. However, exposure to large doses\nof X-rays poses considerable health risks. Therefore, it is crucial\nto reduce the radiation dosage without compromising detection efficiency.\nTo address this concern, we propose an innovative cascade-engineered\napproach that uses two interconnected single-crystal devices to mitigate\ndark current and enhance the detection limit. Using laboratory-grown\nmethylammonium lead bromide (MAPbBr<sub>3</sub>) perovskite single\ncrystals, we engineered devices that significantly reduced detection\nthresholds and improved signal-to-noise ratios (SNRs). The detection\nthreshold dropped from 590 nGy·s<sup>–1</sup> with the\nconventional method to 100 nGy·s<sup>–1</sup> using the\ncascade approach, surpassing the most recent record of 500 nGy·s<sup>–1</sup> achieved for MAPbBr<sub>3</sub> devices under nearly\nidentical conditions. The dark current was halved compared to that\nof conventional devices, and spatial resolution improved from 5.6\n to 8.5 lp·mm<sup>–1</sup>. Imaging trials confirmed improved\nresolution and effectiveness at low doses, highlighting the approach’s\npotential for medical diagnostics that prioritizes reducing radiation\nexposure without compromising image quality. The groundbreaking nature\nof this approach is highlighted by its adaptability across diverse\nelectrical environments and crystal types, as evident in CdTe crystals,\nindicating its potential for widespread utilization in low-dose leakage\nmonitoring and commercial X-ray devices.