基于氮掺杂光纤的高热稳定性，设计了一种FBG温度传感器，实现在高温范围内的稳定监测，并利用数字仿真软件对设计的氮掺杂FBG温度传感器的温度响应特性进行了分析研究。此外，通过构建系统级仿真网络对氮掺杂FBG温度传感器特性进行分析，验证其集成性能。研究结果表明，在温度范围25~1 000 °C，波长为1 550 nm时，氮掺杂FBG传感器的温度灵敏度为15.8 pm/°C。

The realization of single-frequency fiber lasers requires high-gain media. In this work, an Er:YAG crystal-derived silica fiber (EYDSF) was prepared using the melt-in-tube method, whose gain coefficient was up to 2.11 dB/cm using a pump power of 1480 nm. A linearly polarized single-frequency fiber laser was constructed based on a 2-cm-long EYDSF. The optical-to-optical conversion efficiency was 27.0%. A fiber mirror was used at the end of the cavity to reflect the residual pump, which can be absorbed by the EYDSF to further increase the output power. The maximum output power and the slope efficiency of the proposed laser were over 100 mW and up to 22.4%, respectively. To the best of our knowledge, it has the highest output power and the largest slope efficiency, compared with the previous single-frequency fiber lasers based on EYDSFs. In addition, the laser had good polarization and noise performance with a polarization extinction ratio of 25 dB and a relative intensity noise of <-139 dB/Hz. The performance of the proposed fiber laser demonstrates its great potential as a seed source for coherent optical communications, laser combining systems, and other fields.

In this Letter, the optical amplification characteristics of the home-made Bi/P co-doped silica fiber were systematically explored in the range of 1270–1360 nm. The maximum gain of 24.6 dB was obtained in the single-pass amplification device, and then improved to 38.3 dB in the double-pass amplification device for -30dBm signal power. In addition, we simultaneously investigated the laser performance of the fiber with the linear cavity. A slope efficiency of 16.4% at ∼1313nm was obtained with a maximum output power of about 133 mW under the input pump power of 869 mW at 1240 nm. As far as we know, it is the first laser reported based on the bismuth-doped fiber in China.

采用万能拉力试验机测试了不同预制棒预处理工艺、拉丝速度及在线主动控温退火工艺下单模石英光纤的平均拉断力。采用反射式光学显微镜、扫描电子显微镜表征了不同条件下光纤预制棒及光纤表面微观形貌，分析研究了光纤拉断力的影响因素。结果表明：随着拉丝速度逐渐增加，光纤平均拉断力呈下降趋势；通过对预制棒进行火焰抛光与梯度降温处理，优化主动控温退火工艺同时降低拉丝速度，光纤平均拉断力由无任何处理的36.69 N增长到68.28 N，拉断力提高了86%。

We fabricate a high-performance Bi/Er/La co-doped silica fiber with a fluorescence intensity of -33.8dBm and a gain coefficient of 1.9 dB/m. With the utilization of the fiber as a gain medium, a linear-cavity fiber laser has been constructed, which exhibits a signal-to-noise ratio of 74.9 dB at 1596 nm. It has been demonstrated that the fiber laser has a maximum output power of 107.4 mW, a slope efficiency of up to 17.0%, and a linewidth of less than 0.02 nm. Moreover, an all-fiber single-stage optical amplifier is built up for laser amplification, by which the amplified laser power is up to 410.0 mW with pump efficiency of 33.8%. The results indicate that the laser is capable of high signal-to-noise ratio and narrow linewidth, with potential applications for optical fiber sensing, biomedicine, precision measurement, and the pump source of the mid-infrared fiber lasers.