Isothermal formation kinetics of nanocrystals in LiNb_(0.5)Ta_(0.5)O_3 glass

摘要

We report an isothermal formation kinetics of nanocrystals in LiNb_(0.5)Ta_(0.5)O_3 (LNT) glass prepared by the polymerized complex sol-gel process with no addition of glass former. It is observed that the LNT glass transforms into rhombohedral LNT crystal at an elevated temperature and most crystal grains are confined within the size of ~30 nm. We have determined that the formation mechanism of nanocrystals is the diffusion-controlled growth with a constant nucleation rate, based on the Avrami exponent n ~2.5 in Johnson-Mehl-Avrami equation.