The spectroscopic properties of Er3+-doped tellurite glasses were investigated and a 1 wt.% Er3+-doped tellurite fiber was fabricated for L-band lasers. Wavelength-tunable fiber lasers in a linear cavity based on Littrow configuration were developed and studied with different gain fiber lengths as well as output coupling ratios. Wavelength tunable range of 38 nm from 1589–1627 nm was achieved in the experiment with a 3-m Er3+-doped tellurite fiber laser pumped at 1570 nm. A maximum output power of 52.4 mW was obtained at 1614 nm. Compared to L-band Er3+-doped silica fiber lasers, the demonstrated Er3+-doped tellurite fiber lasers exhibit much higher optical signal-to-noise ratio (>30 dB), even at the longest operating wavelength of 1627 nm. Our simulation shows that the laser wavelength can be further extended to 1634 nm if the tellurite fiber loss is improved and the fiber cavity is optimized.

中文翻译：

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L 波段波长可调 ${\rm{Er^{3+}}}$ 掺杂的碲酸盐光纤激光器

研究了 Er3+ 掺杂的碲酸盐玻璃的光谱特性，并为 L 波段激光器制造了 1 wt.% Er3+ 掺杂的碲酸盐光纤。开发并研究了基于 Littrow 配置的线性腔中波长可调谐光纤激光器，其具有不同的增益光纤长度和输出耦合比。在实验中使用 1570 nm 泵浦的 3-m Er3+ 掺杂碲酸盐光纤激光器实现了 1589-1627 nm 的 38 nm 波长可调范围。在 1614 nm 处获得了 52.4 mW 的最大输出功率。与 L 波段 Er3+ 掺杂石英光纤激光器相比，所展示的 Er3+ 掺杂亚碲酸盐光纤激光器表现出更高的光信噪比 (>30 dB)，即使在 1627 nm 的最长工作波长下也是如此。