Sr_(3)Gd(BO_(3))_(3)∶Dy^(3+)/RE^(3+)(RE=Tb,Eu)晶体的生长、发光性质及能量传递

Crystal Growth,Spectral Properties and Energy Transfer Mechanisms of Sr_(3)Gd(BO_(3))_(3)∶Dy^(3+)/RE^(3+)(RE=Tb,Eu)Crystals

黄光激光在医疗美容、原子冷却与捕获、激光雷达等领域具有潜在的应用前景,因此,黄光激光器的研究具有重要意义。Dy^(3+)因其^(4)F_(9/2)→^(6)H_(13/2)辐射跃迁而成为黄光激光的最佳激活离子,但是其在可见光波段为自旋禁戒跃迁,导致其吸收截面和发射截面都很小,从而引起黄光激光输出困难。本文通过提拉法成功生长了Dy^(3+)∶Sr_(3)Gd(BO_(3))_(3)(缩写Dy^(3+)∶SGB)、Dy^(3+)/Tb^(3+)∶SGB和Dy^(3+)/Eu^(3+)∶SGB晶体,通过室温偏振吸收谱、发射谱、荧光衰减曲线以及Judd-Ofelt理论计算分析了其光谱性能和能量传递机制。研究表明,共掺Tb^(3+)和Eu^(3+)增大了Dy^(3+)在黄光波段的发射截面和荧光量子效率,有利于Dy^(3+)的黄光输出。此外,证明了Dy^(3+)/Tb^(3+)∶SGB晶体中发生了Dy^(3+)和Tb^(3+)之间相互能量传递过程,Dy^(3+)/Eu^(3+)∶SGB晶体中仅有Dy^(3+)→Eu^(3+)的能量传递过程。

The yellow lasers are of great importance as they have potential applications in the areas such as medical aesthetics,atomic cooling and trapping,and radar.Dy^(3+)is the best activating ion for yellow lasers due to its ^(4)F_(9/2)→^(6)H_(13/2) radiative transition,but its spin-forbidden transition in the visible wavelength leads to a small absorption and emission cross section,which causes difficulties in yellow laser output.In this paper,Dy^(3+)∶Sr_(3)Gd(BO_(3))_(3)(abbreviation Dy^(3+)∶SGB),Dy^(3+)/Tb^(3+)∶SGB and Dy^(3+)/Eu^(3+)∶SGB crystals were successfully grown by the Czochralski method,and their spectral properties and energy transfer mechanisms were analyzed by room-temperature polarization absorption spectra,emission spectra,fluorescence decay curves and Judd-Ofelt theoretical calculations.It is shown that the co-dopant of Tb^(3+)and Eu^(3+)increases the emission cross section and fluorescence quantum efficiency of Dy^(3+)in the yellow emission band,which is favorable to the yellow laser output of Dy^(3+).In addition,it is demonstrated that a mutual energy transfer process between Dy^(3+)and Tb^(3+)occurs in Dy^(3+)/Tb^(3+)∶SGB crystals and only Dy^(3+)→Eu^(3+)in Dy^(3+)/Eu^(3+)∶SGB crystals.