基于高能量耗散型脉冲掺铒光纤激光器的实验研究

Experimental research on high-energy dissipative solitons in an erbium-doped fiber laser

在正色散掺铒光纤激光器中,利用非线性偏振旋转技术实现自启动锁模,得到了具有极大光谱宽度的高能量、无波分裂耗散型脉冲.该耗散型脉冲的形成是腔内增益、损耗、非线性偏振旋转、正色散和其他非线性效应等共同作用的结果,其形成机理与传统的负色散激光器完全不同.当抽运功率为500mW时,该类型脉冲的光谱覆盖了1530—1660nm范围,半高全宽光谱宽度可达42nm以上.脉冲具有极大的正啁啾,其时间带宽积为483,而单脉冲总能量最大可达34.4nJ.

We have employed a nonlinear polarization rotation technique to realize the self-starting passive mode-locking in an erbium-doped fiber laser with positive dispersion. The laser can emit high-energy dissipative solitons without wave-breaking. The pulse-shaping mechanism, which is qualitatively distinct from the conservative solitons in negative dispersion cavity,may originate from the laser gain,loss,NPR,cavity dispersion,or other fiber nonlinearity effects. To our best knowledge,it is the first report on the experimental observations for high-energy wave-breaking-free dissipative solitons forming in a fiber laser with ultra-large net-normal cavity dispersion. The spectrum of these strongly chirped pulses covers the wavelength range from 1530 to 1660 nm. The FWHM width of the spectrum can be as large as 42 nm,and the maximal total energy of a single-pulse is estimated to be ～ 34. 4 nJ.