Room Temperature γ-Rays and X-Ray Detection with CsPbBr₃ Perovskite

Highly sensitive hard radiation detectors operating at room temperature are in high need for a wide variety of applications. The perovskite semiconductor CsPbBr₃ exhibits a high spectral resolution of γ-rays at room temperature. CsPbBr₃ is air-stable, non-hygroscopic, and possesses high effective atomic number Z-eff of 65.9. An overview of the research progress on the bulk CsPbBr₃ crystals studied so far and detector fabrication and characterization of single crystals will be presented. Highly pure CsPbBr₃ single crystals with high quality can be grown using the Bridgman method. CsPbBr₃ perovskite’s defect tolerance tends to screen electrically activated defects, enabling the carriers' remarkable transport properties. Our CsPbBr₃ detector has shown remarkable energy resolving capability under both X and γ rays, particularly in achieving 3.9% (4.8 keV, FWHM) energy resolution for 122 keV ⁵⁷Co γ-ray with good temporal stability. The hole carrier lifetime in CsPbBr₃ detector-grade single crystal was observed to be well over 25 μs. Pixelated devices can resolve ¹³⁷Cs 662-keV γ-rays with ~1% energy resolution. Results from synchrotron X-ray detection experiments with flux of 10⁶ to 10¹² photons/s/mm²at 58.61 keV, operating in current mode, will also be presented.