Advances in Engineering Advances in Engineering features breaking research judged by Advances in Engineering advisory team to be of key importance in the Engineering field. Papers are selected from over 10,000 published each week from most peer reviewed journals.
Allix M, Alahrache S, Fayon F, Suchomel M, Porcher F, Cardinal T, Matzen G.
Adv Mater. 2012 Nov 2;24(41):5570-5.
CNRS, UPR3079 CEMHTI, 1D Avenue de la Recherche Scientifique, 45071 Orléans Cedex 2, France. [email protected].
Transparent polycrystalline ceramics are an emerging class of photonic quality materials competing with single crystal technology for a diverse range of applications including high-energy lasers, scintillating devices, optical lenses, and transparent armour. Polycrystalline ceramics offer several advantages, particularly in the fabrication of complex shapes and large-scale industrial production, and enable greater and more homogenous doping of optically active ions than is possible in single crystals. A limited number of either cubic or nanocrystalline transparent polycrystalline ceramics are known, but require complex and time-consuming synthetic approaches. Here, we show for the first time that fully dense transparent polycrystalline ceramics can be simply obtained by direct and complete crystallization from glass. This is demonstrated for the previously unreported composition, BaAl4O7 , which exhibits two orthorhombic polymorphs with micrometer grain size, both optically transparent in the visible range. This innovative synthetic route to transparent polycrystalline ceramics should facilitate the discovery of new, cost-effective chemical methods for transparent ceramic applications.
