Purcell-enhanced X-ray scintillation

Abstract: Scintillation materials convert high-energy radiation to optical light through a complex multi-stage process. The last stage of the process is light emission via spontaneous emission, which usually governs and limits the scintillator emission rate and light yield. For decades, the quest for faster emission rate and greater light yield motivated the frontier of scintillators research to focus on developing better materials and dopants. Here, we experimentally demonstrate a fundamentally different, recently proposed concept for enhancing the scintillation rate and yield: the Purcell effect. The Purcell effect is a universal enhancement mechanism for spontaneous emission by engineering the optical environment. In scintillators, such an enhancement arises from engineering the nanoscale geometry within the scintillation bulk, which thus applies universally to any scintillating material and dopant. We design and fabricate a thin multilayer nanophotonic scintillator, demonstrating Purcell-enhanced scintillation, achieving a 50% enhancement in emission-rate and an 80% enhancement in light yield. We demonstrate the potential of our device for realizing these enhancements in real-life settings for X-ray applications, also due to the robustness of the nanophotonic design to fabrication disorder. Our results show the bright prospects of bridging nanophotonics and scintillators science, toward reduced radiation dosage and increased resolution for high-energy particles detection.