Stable Zero-Thermal Quenching Cover Wide Temperature Range Achieves in Cerium Doped Ky3f10 Ultraviolet Fluorescent Single Crystal

The pure and 2 mol% Ce 3+ ions doped KY 3 F 10 (Ce: KYF) single crystals were successfully grown in a vacuum by spontaneous nucleation of the vertical Bridgman method. Ce: KYF single crystal had high crystalline quality and transmittance, and the cutoff absorption edge was significantly red shifted. The broad band emission centered at 360 nm (λex = 300nm) were both observed in them, while a three-fold increased emission intensity was seen when Ce 3+ ions are doped. Combining with a 280 nm chip, Ce: KYF crystal could effectively converted the light of the chip to its luminescence and show high luminous efficiency of 128 lm/W at the driven current of 300 mA. It was a surprise that Ce: KYF crystal exhibited stable zero-thermal quenching in the UV band which covered the wide temperature range of 298 K to 573 K while the pure one has the normally thermal quenching property. The possible mechanism for the luminescent properties and thermal stability was discussed. The superior thermal stability of Ce: KYF single crystal may be ascribed to the existence of the intrinsic defects. Ce: KYF single crystal will have wide application prospect as an excellent UV fluorescent material with high thermal stability