SEMINAR 
Key Laboratory of Transparent Opto-fuctional Inorganic Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences 
中国科学院上海硅酸盐研究所透明光功能无机材料重点实验室 

　　Inorganic scintillation materials: new achievements, challenges and opportunities 

　　Speaker 

　　中国科学院外国特聘研究员 

　　Prof. Martin Nikl  

　　Institute of Physics AC CR, Cukrovarnicka 10, 16253 Prague, Czech Republic 

　　时间：5月30日 （周五）9:00 AM 

　　地点：4号楼3楼会议室 

　　联系人：潘裕柏（2820） 

　　Brief introduction: Prof. Martin Nikl is the Chair of the Dept. of Optical Materials, the member and vice-chair of the Institute Board, Deputy Director for targeted research, Institute of Physics, Academy of Sciences of Czech Republic. His research interests are Luminescence and scintillation materials, energy transfer and storage phenomena in scintillation mechanism, physics of defects, luminescence of excitons, nanoaggregates, and quantum dots. In 2013, he got the excellency award from President of Academy of Sciences of Czech Republic. Prof. Martin Nikl has been the Chairmen of some international conferences. He is the member of the Editorial Board of the Optical Materials, Radiation Measurement and Measurement Science and Technology. He has published 570 papers in the refereed impacted international journals and six chapters in books. He is the author and co-author of 35 invited keynote and plenary lectures at International Conferences. His publications received more than 5860 citations (Scopus, auto-citations excluded), Hirsch factor, H=44.  

　　Abstract: Last two decades were characterized by an intense R&D in the field of oxide based scintillators and phosphors [1] which provided new material solutions for medical and industrial imaging, high-tech an high energy physics instrumentation and geophysical explorations. In high energy physics the radiation hard PbWO₄-based single crystal has been developed and extensively used in new generation of electromagnetic calorimeter detectors, namely in LHC in CERN where Higg’s boson has been recently experimentally confirmed. New material families appeared also in halide materials, namely the ultraefficient Ce-doped LaX₃ (X=Cl,Br). Revival of Eu-doped SrI₂ occurred due to its excellent energy resolution needed in nowadays homeland security measures. Afterglow problem in Ce-doped orthosilicates and CsI:Tl was under instantaneous attention and successful codoping strategies have been revealed. Depending on particular material system the single crystals, optical ceramics and micro or nano-powders have been prepared and systematically tested. Strategies to reveal new promising material compositions have been mostly set on an experimental combinatorial research at powders, thin films or small-size single crystal combined further with theoretical predictions and defect formation energies calculations. New insights have been obtained also regarding the scintillator nonproportionality. 

　　At the same time, new high figure of merit materials have been obtained in the form of solid solutions, where the characteristics improvement appeared as a non-trivial consequence of mixing the known limit compositions and more detailed understanding was achieved in due course in subsequent profound studies. The examples are e.g. LYSO:Ce, LGSO:Ce, GGAG:Ce single crystals, GYGAG:Ce optical ceramics and single crystals. Departure from stoichiometric composition revealed nonstochiometric SrHfO₃ powders with excellent X-ray phosphor characteristics.  

　　This presentation will review the keypoints of success for some of the material systems mentioned above. In some of them our laboratory has been involved together with numerous collaborators from different countries incl. China. It will stress the need of correlated use of different experimental techniques combined further with theoretical calculations and give some hints which might be useful for systematic research of this kind also in other material groups. 

　　References:  

　　1.M. Nikl, A. Vedda and V.V. Laguta, Single-crystal scintillation materials. In: Springer Handbook of Crystal Growth. Eds: G. Dhanaraj, K. Byrappa, V. Prasad, M. Dudley. Springer Verlag 2010. ISBN: 978-3-540-74182-4. Chapter 50, pp. 1663-1700