Transparent glass-ceramics functionalized by dispersed crystals

Transparent glass ceramics (TGCs) with minimized scattering loss offer the combined characteristics of both glasses and (transparent) ceramics. The functionalities of the dispered crystals make TGCs a new generation of tailorable optical materials with a wide range of applications from optics to photonics. Most of conventional glass ceramics (GCs), e.g., silicate glass ceramics, contain crystals involving both network formers and modifiers, and they are known for their superior mechanical/thermal performances. In this paper, we pay more attention to those TGCs containing crystalline phases composed of only network modifiers, including nanocrystals of noble metals, metal fluorides, oxides, chalcogenides, etc. We review recent advances in conventional fabrication methods as well as in emerging techniques for the production of TGCs, such as solid state reaction, sol-gel and laser-induced crystallization. We then discuss the applications of TGCs, particularly the TGCs functionalized by crystals that exhibit various optical functionalities, including photoluminescence, optical nonlinearity, plasmonic absorption, etc. Experimental advances in the use of TGCs for lasers, optical amplifiers and different spectral converters are highlighted. We also anticipate that TGCs will find new applications, and the investigations into TGCs will unravel the mechanism of crystal formation, and hence, lead to the discovery of novel TGC systems.