宽可调谐自起振被动锁模掺铒光纤激光器

Widely Tunable Self-starting Passively Mode-locked Er-doped Fiber Laser

分析了利用非线性偏振旋转效应作为等效可饱和吸收体锁模的原理 ,并用该方法构建起环形腔被动锁模掺铒光纤激光器 ,结合可调谐滤波器腔外滤波的方法实现锁模脉冲波长的连续可调谐 实验中得到自起振、平均输出功率 0 .313mW ,脉冲半极大全宽度 (FWHM) 1.5ps ,中心波长15 6 2 .3nm ,重复频率 13.9MHz的稳定被动锁模脉冲序列输出 ,滤波后输出脉冲中心波长在 15 5 3.2～15 71.4nm内连续可调 ,得到谱宽 2 .5nm以下 ,脉宽小于 1.

The physical mechanism of nonlinear polarization rotation as saturable absorber for mode-locking is analyzed in theory. A passively modelocked fiber laser with loop structure is constructed,which is tunable by using tunable filter outside the cavity. Experimentally,self-starting 1.5 ps mode-locked pulse at 13.9 MHz repetition rate with 0.313 mW average output power is obtained,which is centered at 1562.3 nm. Tunable transform limited pulses are obtained from 1553.2 nm to 1571.4 nm with pulse width less than 1.8 ps.