We investigate optical property of polarization-maintaining fiber taper (PMFT) for tunable multi-wavelength laser generation in a fiber ring cavity. A panda-type polarization fiber is fused and tapered into a fiber taper with a diameter of about 2.5 μm. Optical and thermal properties of the PMFT are investigated theoretically and experimentally. As combined with a polarization dependent isolator, tunable multi-wavelength fiber laser operation is achieved by controlling of polarization-dependent loss in the fiber ring cavity. The laser wavelength number can be switched from 1 to 4. The 3 dB bandwidths of laser spectra are less than 0.05 nm for all wavelength numbers, with a maximum OSNR of about 54 dB. For single-wavelength laser operation near 1561.66 nm, the measured wavelength and power fluctuations are < 0.02 nm and 0.4 dB, respectively.

中文翻译：

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用于可调谐多波长光纤激光器产生的保偏光纤锥度的光学特性

我们研究了保偏光纤锥度 (PMFT) 的光学特性，用于在光纤环形腔中生成可调谐多波长激光。将熊猫型偏振光纤熔合并逐渐变细成直径约2.5μm的光纤锥度。从理论上和实验上研究了 PMFT 的光学和热性能。与偏振相关隔离器相结合，可调谐多波长光纤激光器操作是通过控制光纤环腔中的偏振相关损耗来实现的。激光波长数可在1-4之间切换。所有波长数的激光光谱3dB带宽均小于0.05nm，最大OSNR约为54dB。对于 1561.66 nm 附近的单波长激光操作，测得的波长和功率波动分别 < 0.02 nm 和 0.4 dB。