掺铥氟磷玻璃的结构、热学性质和光谱性质

制备了不同Al(PO3)3含量的掺铥系列氟磷玻璃,研究了其结构、热稳定性和光谱性质。随着Al(PO3)3含量的增加,该系列玻璃的密度降低,折射率增加,差热分析表明,转变温度、析晶起始温度、析晶峰温度和熔化温度增加。Al(PO3)3摩尔浓度在7%~9%时析晶稳定性最佳。采用归一化的拉曼光谱分析了材料的结构和声子状况,对于该系列氟磷玻璃,Al(PO3)3含量的增加不会影响声子能量,但使声子密度增大。测试了样品的吸收光谱,Tm3 的3H6→3F4在第三通信窗口的L波段有明显吸收。与在其它玻璃基质中相比,Tm3 的3F4能级对应能量偏高,3H4能级对应能量偏低,使得3H4→3F4跃迁波长较大,接近于增益迁移光纤放大器的放大波长。扎得奥菲而特(Judd-Ofelt)理论分析表明随着Al(PO3)3含量增加,离子强度参量Ω2增大,Ω6保持相对稳定,Tm3 的能级寿命降低。

Structure, Thermal Properties and Spectral Properties of Tm3 + -Doped Fluorophosphate Glasses

Fluorophosphate glasses with various Al(PO3)3 content were prepared, and their structure, thermal properties and spectral properties were studied. For these glasses, with the increment of Al(PO3)3 content, the density decreased while the refractive index increases, and transition temperature, the onset and maximum of the crystallization peak temperature and melt temperature increased which were suggested by differential scanning calorimetry. These glasses exhibited the best resistance against crystallization with 7%～9% mole concentration Al(PO3)3 content. Normalized Raman spectrums were used to analyze structure and phonon status. For these glasses the increment of Al(PO3)3 content did not affect phonon energy but resulted in the augment of phonon density. Absorption spectrums were measured. 3H6→3F4 exhibited absorption at L band of the third communication window. Compared with the Tm3+ excited states in other glass system, 3F4 energy level of Tm3+ in these glasses was slightly higher and 3H4 energy level was slightly lower, so it could be predicted that emission band of 3H4→3F4 transition was similar to the amplified band of the gain-shift Tm3+ doped fiber amplifier with a relatively long wavelength. Analyses with Judd-Ofelt theory suggested with the increment of Al(PO3)3 content, phenomenological intensity parameter Ω2 increased, Ω6 varied little, and the radiative lifetime of Tm3+ excited states decreased.