基于SWNT可饱和吸收体结合Sagnac滤波的调Q掺铒光纤激光器

Q-switched erbium-doped fiber laser based on SWNT saturable absorber combined with Sagnac filter

摘要:

提出并搭建了一种基于单壁碳纳米管可饱和吸收体结合Sagnac环的被动调Q掺铒光纤激光器,对其输出激光特性进行实验研究。采用光沉积法制备了单壁碳纳米管可饱和吸收体,透射率为75%。基于单壁碳纳米管的可饱和吸收特性,搭建调Q激光器,实现谐振腔Q值调节。将Sagnac环形滤波器插入光纤环形腔,Sagnac环结构产生的滤波效应可以对调Q脉冲实现精细度滤波。该激光器工作阈值为800 mW。当泵浦功率为830 mW时,激光器可实现稳定的1530.4 nm激光输出,输出功率为12.3 mW,重复频率为210.7 kHz,对应的脉冲周期为4.76 μs,脉冲宽度为2.19 μs,其最大脉冲能量为58.37 nJ。

Abstract:

The output laser properties of a passive Q-switched Erbium-doped fiber laser based on a saturable absorber of single-walled carbon nanotubes coupled with a Sagnac loop is experimentally investigated. Single-walled carbon nanotube saturable absorbers are created by light deposition with a 75% transmittance. A Q-switched laser is built to modify the resonator"s Q value based on the single-walled carbon nanotubes" saturable absorption properties. When the Sagnac loop filter is placed inside the optical fiber ring cavity, the Q-switched pulses can achieve fine filtering thanks to the filtering effect produced by the Sagnac loop structure. The Q-switched laser"s operating threshold is 800 mW. The stable laser can produce a 1530.4 nm laser with an output power of 12.3 mW, repetition frequency of 210.7 kHz, corresponding pulse period of 4.76 ms, and pulse width of 2.19 ms when the pump power is 830 mW. It has a 58.37 nJ maximum pulse energy.