Luminescence properties of Cr3+:Y3Al5O12 nanocrystals

The Cr3+-doped Y3Al5O12 (YAG) nanocrystalline powders were prepared by the Pechini method. The structural and phase evolution studies were performed using X-ray powder diffraction (XRD) method. The TEM images were taken in order to characterize the grain size and morphology of the Cr:YAG nanocrystals. Their excitation and luminescence spectra were investigated. It was found that luminescence properties of the Cr:YAG nanocrystals were strongly affected by size of the particles. With increasing the grain size the electron-phonon coupling decreases whereas the crystal-field strength increases.