Combinatorial Strategy Toward Fast and Efficient Scintillators

72888S03-I Ultra-fast (sub-nanosecond), highly efficient scintillators are needed for many time-resolved energetic photon detections. Near-band-edge emission semiconductor scintillators provide the best opportunity to reach these goals. However, thermal quenching has been a serious problem that strongly deteriorates the light output of these materials at room temperature. Thermal quenching relates directly to the materials¿ defect structure, band structure, and excitonic states. In this project, advanced combinatorial material search strategy will be used to identify possible compositions in wide-bandgap semiconductor materials (including ZnO, HgI2, and PbI2) through band structure engineering, bandgap engineering, and n-type/p-type engineering. Using these compositions, novel ultra-fast and highly efficient energetic photon detectors will be developed. Phase I will identify the best scintillator compositions in a ZnO system, through extensive doping using the combinatorial strategy. An ultrafast scintillator (<1 ns), with light output comparable to that from a current insulator scintillator, will be an expected result. Commercial Applications and Other Benefits as described by awardee: Potential applications include nuclear detections, dynamic nondestructive tests, fast medical imaging, and micro-crystallography.