Tm3+‐doped mixed sesquioxide transparent ceramics are attractive candidates for the generation of robust ~2.1 μm lasers. In this paper, laser‐quality Tm:(Lu0.8Sc0.2)2O3mixed sesquioxide ceramics were shaped for the first time by gelcasting of well‐dispersed nanopowders, which were obtained using a modified coprecipitation method. The dispersibility of starting nanopowders was largely improved using alcohol‐water solvent. The rheological properties of slurries were optimized for gelcasting. We also investigated the densification behavior of the gel‐casted green compacts. In contrast to the dry‐pressing route, it was found that gelcasting could yield more homogeneous and transparent ceramics. The optical in‐line transmittance of the ceramic rod 12 mm in length was as high as 80.3% at 2090 nm. Upon pumping the ceramic rod by 796 nm diode laser, a 1.88 W
High‐entropy ceramics have been widely explored and extensively studied since the first demonstration of the configuration entropy stabilized reversible transitions between multiple and single phases by Rost et al. in 2015. Most of the current research on high‐entropy ceramics has focused on properties like thermal conductivity, thermoelectricity, structures, and others. Some recent studies have extended the high‐entropy concept to the field of transparent ceramics. We reviewed these papers and proposed four potential ceramics groups for high‐entropy transparent ceramics including fluoride ceramics, fluorite‐deficient and/or ordered pyrochlore A2B2O7ceramics, garnet ceramics, and sesquioxide ceramics. In this article, we review ceramic powder synthesis, the fabrication of transparent ceramics, high‐entropy ceramics, and limited cases of high‐entropy transparent ceramics for each category. High‐entropy transparent ceramics with diverse compositions and structures will provide more possibilities for functional transparent ceramics in the future.
more » « less- NSF-PAR ID:
- 10447443
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- International Journal of Applied Ceramic Technology
- Volume:
- 19
- Issue:
- 2
- ISSN:
- 1546-542X
- Page Range / eLocation ID:
- p. 644-672
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract CW laser at 2090 nm was acquired with a slope efficiency of 24.6% (with respect to the input pump power). -
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