Scintillation properties and electronic structure of the intrinsic and extrinsic mixed elpasolites Cs 2 Na RBr 3I 3 ( R = La, Y)
Scintillators attract wide research interest for their distinct applications in radiation detection. Elpasolite halides are among the most promising scintillators due to their high structural symmetry and good scintillation performance. A better understanding of their underlying scintillation mechanism opens up possibilities in scintillator development. In this work, we employ a variety of experimental techniques to study the two mixed-anion elpasolites Cs 2Na RBr 3I 3 ( R = La, Y). The emission of intrinsic Cs 2Na RBr 3I 3 with a light yield ranging from 20 000 to 40 000 ph / MeV is dominant by self-trapped exciton emission. Partial substitution of R with Ce introduces a competing emission, the Ce 3+ 5d-to-4f radiative transition. Ab initio calculations are performed to investigate the electronic structures as well as the binding energies of polarons in Cs 2Na RBr 6. The calculated large self-trapped exciton binding energies are consistent with the observed high light yield due to self-trapped exciton (STE) emission. The unique electronic structure of halide elpasolites as calculated enhances the STE stability and the STE emission. The highly tunable scintillation properties of mixed-anion elpasolites underscore the role of their complex scintillation mechanism. Furthermore, our study provides guidance for the designmore »
- Authors:
-
[1];
[2];
[1];
[3];
[1];
[1];
[2]
- Univ. of Tennessee, Knoxville, TN (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Stanford Univ., Stanford, CA (United States)
- Publication Date:
- Grant/Contract Number:
- AC05-00OR22725
- Type:
- Accepted Manuscript
- Journal Name:
- Physical Review Applied
- Additional Journal Information:
- Journal Volume: 5; Journal Issue: 2; Journal ID: ISSN 2331-7019
- Publisher:
- American Physical Society
- Research Org:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Org:
- USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
- OSTI Identifier:
- 1244201
- Alternate Identifier(s):
- OSTI ID: 1238410