Defect Dynamics Governed Radiation Hardness in Single‐Crystal CsPbBr ₃ γ‐Ray Detectors

Abstract CsPbBr 3 is a reliable and cost‐effective semiconductor material with significant potential for radiation detection applications. However, a crucial challenge is maintaining both high performance and radiation stability, particularly under extreme irradiation conditions. Here, the intrinsic origin of the exceptional radiation hardness of CsPbBr 3 single‐crystal detectors is revealed by integrating performance changes with the evolution of point defects. It is shown that the detectors maintain exceptional radiation hardness under 60 Co γ‐radiation (1.17 and 1.33 MeV) doses as high as 5 Mrad, with the crystal structure remaining stable, and no degradation, decomposition or phase segregation is observed. The combination of pulse height spectra response and deep level transient spectroscopy demonstrates that CsPbBr 3 detectors exhibit a self‐healing capability through efficient defect migration at room temperature. Low‐dose irradiation (≤500 krad) passivates intrinsic defects and reduces trap density, while high‐dose irradiation (≥1 Mrad) generates new defects and degrades energy resolution. The self‐healing behavior is attributed to the defect repair mechanism of radiation‐induced damage in CsPbBr 3 through efficient defect migration. These findings position CsPbBr 3 as a leading candidate for radiation‐hardened applications and provide critical insights into self‐healing semiconductor materials for extreme environments.