Bright, Fast and Durable Scintillation from Colloidal Quantum Shells

Efficient, fast, and robust scintillators for ionizing radiation detection are crucial in various fields, including medical diagnostics, defense, and particle physics. However, traditional scintillator technologies face challenges in simultaneously achieving high brightness and high-speed operation. In this work, we introduce heterostructures of colloidal quantum shells as X-ray scintillators, which combine efficiency, speed, and long-term stability all together [1]. The quantum shells exhibit light yields, a critical efficiency parameter of a scintillator, as high as 70,000 photons MeV⁻¹ at room temperature, surpassing those of the best inorganic ceramic scintillators. The remarkable light yield of quantum shells is enabled by high multiexciton radiative efficiency resulting from long Auger - Meitner lifetimes exceeding 10 ns. Radioluminescence decay of the quantum shells is measured under pulsed x-rays, exhibiting a lifetime of 2.5 ns with a sub-100 ps rise time. Furthermore, we do not observe any afterglow or slow scintillation lifetime, critical for fast imaging and timing applications. Importantly, the quantum shells maintain their scintillation steadily even under extremely high x-ray doses (> 10⁹ Gy), which is million times larger than typical dose limits of fast organic scintillators. Finally, we showcase quantum shells as x-ray imagers, achieving a fine spatial resolution of 28 line pairs per millimeter. Overall, efficient, fast, and durable scintillation make quantum shells appealing in applications ranging from ultrafast radiation detection to high-resolution imaging.
[1] B. Guzelturk, B. T. Diroll, J. P. Cassidy, D. Harankahage, M. Hua, X.-M. Lin, V. Iyer, R. Schaller, B. Lawrie, M. Zamkov, Nature Communications 15, 4274 (2024)