An ultrafine frequency linearly tunable single-frequency fiber laser based on the intracavity active tuning is demonstrated. Single-frequency operation can be achieved by an ultrashort cavity and ultranarrow polarization-maintaining fiber Bragg grating. A sub-nanometer-accuracy piezoelectric ceramic actuator with closed-loop mode has been employed to realize the cavity-length active tuning scheme, which can achieve a linear tuning range of >1 GHz with a 3.2-MHz/nm tuning resolution. The periodic tuning repeatability and repeat accuracy show that the scheme can realize linear frequency tuning with great tuning repeatability and high tuning precision.

中文翻译：

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基于腔内主动调谐的超细频线性可调单频光纤激光器

展示了一种基于腔内主动调谐的超细频率线性可调单频光纤激光器。单频操作可以通过超短腔和超窄保偏光纤布拉格光栅实现。已采用具有闭环模式的亚纳米精度压电陶瓷致动器来实现腔长有源调谐方案，该方案可以实现 >1 GHz 的线性调谐范围，调谐分辨率为 3.2 MHz/nm。周期调谐重复性和重复精度表明，该方案可以实现线性频率调谐，调谐重复性好，调谐精度高。