Towards Extremely Low-Dose Photon Counting Perovskite X-Ray Detectors

Halide perovskites are generating enormous excitement for optoelectronic applications. Over recent years, they have been demonstrated to be excellent candidates for direct detectors of X-ray and other high-energy radiation, with hints of photon counting ability. This demonstrates their promise for low-dose medical imaging with low cost detectors, which could revolutionise CT scanning.<br/><br/>Here, I will give an overview of our recent work towards photon counting detectors based on halide perovskites. I will discuss the importance of passivation and interface control, as well as the quality of the single crystal. 2-photon optical imaging allows us to identify buried defects in crystals that otherwise lead to enhanced dark currents, leading to a requirement for extremely high quality crystals. The mode of operation also strongly effects the performance and stability of the device. By combining high quality crystal growth and interface control, we demonstrate photon counting from single pixel devices, and operation from multi-pixel arrays. This work shows promise for future detectors for medical imaging and other applications.