Spectroscopic Studies on Charge Transfer from Ce3+ to Yb3+ in KMgF3: Ce, Yb Nanocrystals*

Nanocrystals of KMgF3 single-doped and codoped with Ce3+ or/and Yb3+ were synthesized separately by the microemulsion method. The X-ray diffraction (XRD) patterns were indexed to show that the KMgF3 crystal system was unchanged. The fluorescent spectra of KMgF3: Ce, Yb polycrystal powders were studied and compared with those of the Ce, Yb doped KMgF3 crystals produced using the high-temperature solid phase method. The diffuse reflection spectra and infrared emission of KMgF3: Ce, Yb were investigated. From the results, the authors could confirm that there were charge transfer processes from Ce3+ to Yb3+ in both KMgF3: Ce, Yb nanocrystals and polycrystal powders.