用同步辐射研究掺Tb^(3+)氟化物K_2GdF_5的光谱和Gd^(3+)-Tb^(3+)能量传递

Synchrotron Radiation Study of The Luminescence and Energy Transfer of Tb^(3+)-doped K_2GdF_5

对比了不同激发波长下水热法合成的K2GdF5∶Tb3+(摩尔分数0.5%)单晶材料的光致发光谱线;监测了5D3→7F6和5D4→7F5的激发谱,给出了几组窄带吸收和3个宽带吸收;分析表明窄带发射为Gd3+的8S7/2→6FJ、8S7/2→6 GJ、8 S7/2→6 DJ、8 S7/2→6 IJ的跃迁,宽带发射为Gd3+的基态7 F6到4f7(8 S)5d组态中的低自旋态的跃迁;此外,还对Gd3+→Tb3+的能量传递和Tb3+之间的交叉弛豫进行了初步分析。

The photoluminescence spectra of K2GdF5：Tb3＋（0.5%,mole fraction） single crystal under various excitations were measured and compared.The room temperature excitation spectra of 5D3→7F6 and 5D4→7F5 transitions exhibited three broad bands and three groups of narrow peaks.The narrow peaks were assigned as 8S7/2→6FJ6GJ,8S7/2→6DJ and 8S7/2→6IJ transition of Gd3＋ and the broad bands were assigned as the absorption from the ground state 7F6 to the low-spin states of 4f7（8S）5d configurations of Tb3＋.The mechanism of energy transfer from Gd3＋ to Tb3＋ and the cross relaxation between Tb3＋ ions were also analyzed.