Bulk Crystal Growth of Cr-doped MgAl2O4 spinel by Czochralski method and properties characterization

Cr3+-doped MgAl2O4 single crystal with size of Ø30 mm × 70 mm, was firstly successfully grown by the Czochralski method and the effective segregation coefficient of Cr3+ was determined. The X-ray powder pattern was studied, and the X-ray rocking curve indicates a high crystalline quality of the grown crystal. The thermal conductivity was measured from 270 K to 370 K, and the optical absorption measurements in the 250-1000 nm spectral regions was performed at room temperature. Furthermore, emission spectra, excitation spectra and fluorescence decay curve of Cr:MgAl2O4 crystal were also recorded.