New 30 GeO2-30 TeO2-15 ZnO-10 Na2CO3-10 CaF2-3 La2O3-x ErF3 (x = 2, 4) glasses have been synthesized and submitted to varied heat treatments to provoke nanocrystallization in their matrix. The Er3+-doped materials containing typically 50 A-sized nanocrystallites have been characterized by DSC, ultrapicnometry, XRD, HRTEM, EDS, SAED, optical spectroscopy and VSM techniques. A Judd-Ofelt analysis could be performed from the absorption spectra and led to refined intensity parameters. The local structural changes around Er3+ cations were mostly evidenced by important modifications of the hypersensitive optical absorption bands (4I15/2 → 2H11/2, 4I15/2 → 4G11/2) and lesser modifications of the emission cross sections and experimental lifetimes. Besides, cycling around the crystallization temperature with a VSM showed some kind of “crossover” between the Curie-Weiss behavior of the Er3+ cations dissolved in the glass and those dissolved in the nanocrystallites, with a striking change of magnetic interactions sign from anti- to ferromagnetic. The crystal field Hamiltonian could be refined in C2 symmetry, thanks to the emission and excitation spectra recorded at 80 K, and the crystal field strength calculated.

中文翻译：

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新型氧氟锗沸石玻璃和微晶玻璃中 Er3+ 离子的 Judd-Ofelt 分析和晶场计算

已经合成了新的 30 GeO2-30 TeO2-15 ZnO-10 Na2CO3-10 CaF2-3 La2O3-x ErF3 (x = 2, 4) 玻璃，并对其进行了各种热处理以在其基质中引发纳米化。Er3+ 掺杂材料通常含有 50 个 A 尺寸的纳米微晶，已通过 DSC、超显微测量法、XRD、HRTEM、EDS、SAED、光谱学和 VSM 技术进行表征。可以从吸收光谱中进行 Judd-Ofelt 分析，并得出精确的强度参数。Er3+ 阳离子周围的局部结构变化主要通过超敏光吸收带（4I15/2 → 2H11/2、4I15/2 → 4G11/2）的重要修改以及发射截面和实验寿命的较小修改来证明。除了，使用 VSM 在结晶温度附近循环显示了溶解在玻璃中的 Er3+ 阳离子的居里-魏斯行为与溶解在纳米微晶中的那些之间的某种“交叉”，磁性相互作用符号从反磁性到铁磁性的显着变化。由于在 80 K 下记录的发射和激发光谱以及计算出的晶体场强，晶体场哈密顿量可以在 C2 对称性中进行细化。