Cascade perovskite single crystal for gamma-ray spectroscopy
Xin Wang, Yuzhu Pan, Yubing Xu, Jingda Zhao, Yuwei Li, Qing Li, Jing Chen, Zhiwei Zhao, Xiaobing Zhang, Byung Seong Bae, Damian C. Onwudiwe, Xiaobao Xu, Wei Lei
Abstract
The halide lead perovskite single crystals (HLPSCs) have great potential in gamma-ray detection with high attenuation coefficient, strong defects tolerance, and large mobility-lifetime product. However, mobile halide ions would migrate under high external bias, which would both weaken the gamma-ray response and cause additional noise. Here, we report the gamma-ray PIN photodiodes made of cascade HLPSCs including both ion-formed and electron-hole-formed electrical junctions that could suppress the ions migration and improve the charges collection. Our photodiodes based on cascade HLPSCs (MAPbBr 3 /MAPbBr 2.5 Cl 0.5 /MAPbCl 3 ) show a wide halide-ion-formed depletion layer of ∼52 μm. The built-in potential along the wide ionic-formed junction ensures a high mobility-lifetime product of 1.1 × 10 −2 cm 2 V −1 . As a result, our gamma-ray PIN photodiodes exhibit compelling response to 241 Am, 137 Cs, and 60 Co; the energy resolution can reach 9.4%@59.5keV and 5.9%@662keV, respectively. This work provides a new path toward constructing high-performance gamma-ray detectors based on HLPSCs.