Optical spectra of Eu2+ ion doped KMgF3 single crystals grown by Bridgman method

High-quality KMgF 3 single crystal containing 0.5 mol% europium (Eu) was prepared by an improved Bridgman method. X-ray diffraction (XRD), photoluminescence spectra and fluorescence lifetime were measured. The results indicate the reduction of Eu 3+ to Eu 2+ in the KMgF 3 single crystal. Under the excitation of 259 nm, 370 nm and 394 nm, the sample has two distinct emissions of Eu 2+ :4f 7 →4f 7 (~363 nm) and 4f 6 5d 1 →4f 7 (~440 nm). The substitution site for Eu ion is confirmed. The optical property investigation result shows that the Eu 2+ doped KMgF 3 single crystal may be used as potential laser media and related materials for optical devices.