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Title: Crystal growth and characterization of undoped and Dy-doped TlPb2Br5 for infrared lasers and nuclear radiation detection
We report results of the crystal growth and characterization of undoped and Dy-doped TlPb2Br5 for applications in infrared (IR) lasers and nuclear radiation detection. TlPb2Br5 (TPB) was synthesized from commercial starting materials of PbBr2 and TlBr and further purified through a combination of zone-refinement and directional solidification. For doping experiments, 2 wt% of DyBr3 was added to the purified TPB material. Crystal growth of TPB and Dy: TPB was carried out in a two-zone tube furnace by a vertical Bridgman method. Following optical excitation at ~1.36um, the Dy: TPB crystal exhibited efficient mid-IR emission bands centered at 2.87um and 4.35um with room-temperature lifetimes of 9.5 ms and 5.2 ms, respectively. The peak emission cross-sections were determined to be ~0.8x10-20 cm2 and ~0.5x10-20 cm2, respectively, which makes Dy: TPB a promising candidate for mid-IR laser applications. Besides its potential as a solid-state laser host, an undoped TPB crystal was also tested for gamma-ray detection. Using Cs-137 and Am-241 sources resulted in energy resolutions for gamma-rays as good as 1-2% (FWHM) at room-temperature under non-optimized conditions.  more » « less
Award ID(s):
1649150
NSF-PAR ID:
10060145
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Journal of crystal growth
Volume:
479
ISSN:
0022-0248
Page Range / eLocation ID:
89-92
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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