Heavily ${{\rm Tm}^{3 +}}$-doped glass fibers are urgently desired for ${\sim}{2}\;\unicode{x00B5}{\rm m}$ single-frequency fiber lasers and high-repetition-rate mode-locked fiber lasers. Here the structure of glass networks was tuned through controlling the numbers of non-bridging oxygens and bridging oxygens by adjusting the composition of the glasses, hence increasing the ${{\rm Tm}^{3 +}}$ doping concentration of germanate glasses. The increased flexibility of the glass networks favors the distribution of ${{\rm Tm}^{3 +}}$ ions to decrease fluorescence quenching, which was confirmed by the experimental and theoretical results. A heavily ${{\rm Tm}^{3 +}}$ (${9.8} \times {{10}^{20}}\;{\rm ions}/{{\rm cm}^3}$)-doped germanate glass was successfully fabricated without quenching by tuning the components of the glass. To the best of our knowledge, the ${{\rm Tm}^{3 +}}$ ion doping concentration is the highest reported level in ${{\rm Tm}^{3 +}}$-doped glasses and fibers. The results suggest that the heavily ${{\rm Tm}^{3 +}}$-doped germanate glass is highly promising for fabricating $\sim 2\; \unicode{x00B5}{\rm m}$ glass fibers with high gain per unit length.

中文翻译：

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可控制的结构剪裁，以在掺有Tm ^3+的德国锗玻璃中增强〜2 µm的发射

重$ {{\ RM的Tm} ^ {3 +}} $掺杂玻璃纤维，迫切期望$ {\ SIM} {2} \; \ {的unicode x00B5} {\ RM米} $单频光纤激光器和高重复率锁模光纤激光器。在此，通过调节玻璃的组成来控制非桥连氧和桥连氧的数量来调整玻璃网络的结构，从而提高了德国玻璃的$ {{\ rm Tm} ^ {3 +}} $掺杂浓度。玻璃网络的增加的柔韧性有利于$ {{\ rm Tm} ^ {3 +}} $离子的分布，以减少荧光猝灭，这已被实验和理论结果所证实。一个严重$ {{\ RM的Tm} ^ {3 +}} $（掺杂$ {9.8} \ times {{10} ^ {20}} \; {\ rm离子} / {{\ rm cm} ^ 3} $的锗酸盐玻璃，无需通过调节玻璃的成分就可以淬火而成功地制成。据我们所知，$ {{\ rm Tm} ^ {3 +}} $的离子掺杂浓度是掺入$ {{\ rm Tm} ^ {3 +}} $的玻璃和纤维中最高的报告水平。。结果表明，掺杂$ {{\ rm Tm} ^ {3 +}} $的锗玻璃对于制造$ \ sim 2 \很有前景。\ unicode {x00B5} {\ rm m} $玻璃纤维，每单位长度的增益高。