Investigating new activators for small-bandgap LaX₃ (X = Br, I) scintillators

Journal Article · 08 December 2017 · Journal of Crystal Growth

DOI: https://doi.org/10.1016/j.jcrysgro.2017.12.015 · OSTI ID:1477492

Rutstrom, Daniel ^[1]; Collette, Robyn ^[2]; Stand, Luis ^[3]; Loyd, Matthew ^[4]; Wu, Yuntao ^[4]; Koschan, Merry ^[5]; Melcher, Charles L. ^[3]; Zhuravleva, Mariya ^[4]

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1. Univ. of Tennessee, Knoxville, TN (United States). Scintillation Materials Research Center and Department of Materials Science and Engineering; UC Berkeley
2. Univ. of Tennessee, Knoxville, TN (United States). Department of Materials Science and Engineering
3. Univ. of Tennessee, Knoxville, TN (United States). Scintillation Materials Research Center, Department of Materials Science and Engineering and Bredesen Center
4. Univ. of Tennessee, Knoxville, TN (United States). Scintillation Materials Research Center and Department of Materials Science and Engineering
5. Univ. of Tennessee, Knoxville, TN (United States). Scintillation Materials Research Center

In this study, luminescence and scintillation properties of Bi³⁺, Sb³⁺, and Eu²⁺-doped LaI₃ and LaBr₃ were explored. Out of the three dopants investigated, Eu²⁺ was the most promising new activator for small-bandgap LaX₃ (X = Br, I) and was further studied in the mixed-halide LaBr_3-xI_x. Crystals were grown from the melt using the vertical Bridgman method. LaBr₃:Eu²⁺ 0.5% (mol) had the most favorable scintillation properties with a light output of 43,000 ph/MeV and 6% energy resolution at 662 keV. Performance of LaBr_3-xI_x:Eu²⁺ worsened for most samples as iodide concentration was increased. Finally, room-temperature scintillation of LaI₃:Eu²⁺ 0.1% and 0.5% was observed and is the first case of room-temperature emission reported for doped LaI₃.

• Research Organization: Nuclear Science and Security Consortium, Berkeley, CA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA); USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation (NA-20)
• Grant/Contract Number: NA0003180
• OSTI ID: 1477492
• Journal Information: Journal of Crystal Growth, Journal Name: Journal of Crystal Growth Journal Issue: C Vol. 483; ISSN 0022-0248
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English