双波长1.0 μm调Q和1.5 μm增益开关脉冲光纤激光器

Dual-Wavelength 1.0 μm Q-Switched and 1.5 μm Gain Switched Pulsed Fiber Laser

采用铒镱共掺光纤,实现了一种双波长1.0μm调Q和1.5μm增益开关脉冲光纤激光器。实验装置是一个双环腔结构,两环的公共端共用一段铒镱共掺光纤。1.0μm调Q脉冲通过未抽运铒镱共掺光纤的可饱和吸收效应产生。而铒镱共掺光纤对1.0μm调Q脉冲的再吸收会周期性调制铒离子的反转粒子数,从而产生重复频率相等的1.5μm增益开关脉冲。随着抽运功率的增加,这两种脉冲的重复频率从5.4kHz增加到11.7kHz。1.5μm脉冲相对1.0μm脉冲有一定的延迟,并且延迟时间随着抽运功率的增大而不断减小。在最大抽运功率处,1.0μm脉冲宽度、单脉冲能量和最大平均输出功率分别是5.3μs、402.6nJ和4.7mW,而对于1.5μm脉冲,分别是4.6μs、374.4nJ和4.4mW。

A dual-wavelength 1.0 μm Q-switched and 1.5 9m gain-switched pulsed fiber laser is demonstrated by using a single Er/Yb co-doped gain fiber. Experimental setup consists of two loop resonators with one common branch including the Er/Yb co-doped fiber. The 1. 0 μm Q-switched pulses are generated via the saturable absorption effect of the unpumped Er/Yb co-doped fiber, whereas a reabsorption of 1.0μm Q-switched pulses from the Yh ions modulates the population inversion of Er ions periodically to generate 1.5 gm gain-switched pulses at the same repetition rate of 1.0 μm Q-switched pulses. With the increase of pump power, the repetition rates of both pulses vary from 5.4 kHz to 11.7 kHz. However, the 1.5 μm pulses have a delay relative to 1.0 μm pulses, and the delay decreases with the increase of pump power. At the maximum pump power, the pulse duration, single pulse energy and average output power for 1.0 μm pulses are 5.3 μs, 402.6 nJ and 4.7 mW respectively, whereas they are 4.6 μs, 374.4 nJ and 4.4 mW respectively for 1.5 μm pulses.