Optical Active Nano‐Glass‐Ceramics

This paper reviews the synthesis and characterization of several transparent glass‐ceramics with optical active nanocrystals. Glass‐ceramics containing ferroelectric S r x B a 1‐x N b 2 O 6 nanocrystals with an ellipsoidal shape show optical phase modulations in the presence of alternative electric fields. In the glass‐ceramics with B a 2 T i S i 2 O 8 ( BTS ) nanocrystals, BTS crystalline layers with a thickness of approximately 120 nm are formed at the surface and ellipsoidal‐shaped crystallites with a diameter of 100–200 nm are dispersed in the glass matrix. Some T e O 2 ‐based and G e O 2 ‐based glasses show a prominent nanocrystallization. RE ‐doped C a F 2 nanocrystals are patterned in a spatially selected region by laser irradiations. The size, morphology, and dispersion state of nanocrystals should be carefully checked in each glass system and composition. The basic concept for the design of glass system and composition is also discussed. Some data on optical active performances in transparent glass‐ceramics with nanocrystals were introduced.