Crystal growth of LiF/LiYF_4 eutectic crystals and their luminescent properties

摘要

Undoped and 0.5 mol% Ce-doped LiF-LiYF_4 eutectic crystals were grown by the micro-pulling-down method at different growth rates. The SEM images of all the eutectic crystals showed LiF with rod-like structure in the LiYF_4 matrix. The diameter of the rod phase systematically decreased with the increase of the growth rate. The radioluminescence spectra of cerium doped crystal under alpha-ray excitation showed emission peak at 325 nm related to Ce~(3+) 5d-4f transition. The white part in the cathodoluminesccnce image is considered to be due to Ce~(3+) ion in LiYF_4 phase, according to the scanning electron microscopy (SEM) image in the same region.