Q-switched Yb Doped Fiber Ring Laser with a M-Z Interferometer

An all-fiber Yb-doped Q-switched fiber ring laser system is reported. The laser system uses an all-fiber M-Z interferometer which plays both roles of Qswitch and tunable filter. Theoretical analysis and primary experimental results are given. A continuous tuning range 6fover 7 nm (from 1035 nm to 1042 nm) and a very stable pulse train with repetition rates exceeding 3 kHz and pulse width of 1.1μs were obtained. The laser system shows low cavity loss and is stable.     

All-fiber actively Q-switched fiber laser tuned by a pair of temperature controlled fiber Bragg gratings

We report an all-fiber actively Q-switched erbium-doped fiber laser, where the linear laser cavity mirrors are composed of two fiber Bragg gratings (FBGs). The laser oscillation wavelength could be tuned by this pair of temperature controlled FBGs. The Q-switching is achieved by an all-fiber phase modulation device. Using this system, we could obtain stable Q-switched laser pulses output, which could be optimized by tuning the reflection wavelengths of the two FBGs to be adjacent to each other. Instead of being modulated by the FBG filter in high-speed oscillation, this fiber laser system is operating in the Q-switched regime using an all-fiber phase modulator, producing a more stable laser output spectrum.     

Experimental observation of bright-dark pulse emitting in an all-fiber ring cavity laser

We demonstrate the emission of bright pulse and dark pulse in a simple all-fiber ring cavity laser by using self-pulsing technique. The switching between bright pulse and dark pulse can be realized by properly rotating the polarization controller (PC). Meanwhile, the bright-dark pulse can also be generated in the fiber laser and is experimentally verified to be on two different orthogonal polarization axis of the cavity fiber. Our experimental results show that the bright pulse, the dark pulse or the bright-dark pulse can be obtained in an all-fiber laser by using self-pulsing technique.     

基于光纤光栅谐振腔的掺镱全光纤激光器设计(英文)

采用数值分析方法分析了光纤长度、后腔镜反射率等因素对激光器输出阈值泵浦功率、输出功率的影响,为全光纤激光器的优化设计提供了理论基础.在设计过程中采用光纤光栅作为光纤激光器的反馈与选频腔镜,通过锥度光纤实现了泵浦模块与掺镱双包层光纤之间的低损耗连接以及高效率的泵浦激光功率传输,成功研制了具备稳定窄化线宽激光输出的掺镱全光纤激光器.实验得到了波长峰值在1 082 .50 nm,谱线宽度0 .113 nm,最大输出功率8 .5 W,泵浦阈值功率0 .8 W,斜率效率为70 .8 %的稳定激光输出.     

Er^3＋／Yb^3＋掺杂全光纤环形激光器

本文报道利用Er~(3+)/Yb~(3+)掺杂单模光纤首次研制成功的环形谐振腔结构的可调谐(调谐范围宽于70nm)全光纤激光器的设计原理及其实验结果.     

全光纤激光阵列主动相位控制技术研究进展

全光纤激光阵列主动相位控制利用全光纤网络实现阵列激光的活塞相位内部探测与控制,具有结构紧凑、无需外部反馈光学器件和易于扩展等优点,是大阵元规模光纤激光相干合成重要发展方向之一。采用全光纤相位探测结构,介绍了全光纤激光阵列主动相位控制技术的系统原理和利用光纤耦合器实现相位锁定的过程,总结了全光纤激光阵列主动相位控制关键技术,通过优化算法实现全光纤激光阵列主动相位控制验证实验。探讨了在全光纤结构主动相位控制中π相位模糊问题及解决方法,给出了利用双波长探测实现消除π相位模糊问题的仿真结果。最后梳理了全光纤激光阵列主动相位控制研究现状,并从路数扩展、功率提升和应用等方面进行了展望。     

67.9W高功率全光纤白光超连续谱激光器

利用自主研发的全光纤被动锁模激光器以及高功率光纤模场匹配器,将145 W的皮秒脉冲耦合进国产光子晶体光纤,实现了67.9 W的高功率全光纤结构白光超连续谱输出,光谱范围为500~1700nm,10dB光谱宽度大于1000nm(泵浦波长除外)。整个激光器系统的光-光(半导体泵浦源输出激光-超连续谱输出激光)转化效率达到33.8%。     

基于光纤合束器件的高功率全光纤相干合成技术研究进展与展望

介绍了目前研究中相干合成多采用空间结构的研究现状,分析了空间结构的相干合成方案需要复杂的光路调节且长时间工作稳定性欠缺,肯定了基于光纤合束器件的全光纤激光相干合成在相干合成光源中的稳定性与实用性,梳理了近年来基于光纤合束器件的全光纤激光相干合成方案,分别介绍了基于光纤耦合器、光子灯笼、相干信号合束器以及基于自成像效应实现全光纤合束的技术方案及研究现状,分析了不同光纤器件目前的主要限制因素和发展瓶颈,并展望了未来的发展方向。     

Novel discretely tunable narrow linewidth fiber laser with uniform wavelength spacing

A novel configuration of the tunable fiber laser with uniform wavelength spacing in dense wavelength division multiplexing (DWDM) application is proposed. The ring type tunable fiber laser consists of an all-fiber comb filter which determines the wavelength spacing, and a piece of adjustable fiber grating to select the discrete lasing wavelength for WDM application. The proposed all-fiber ring type tunable laser has potential application in the DWDM and other optical systems due to its advantages such as narrow linewidth, easy tuning, uniform wavelength interval, etc..     

Widely ultra-narrow linewidth 104 nm tunable all-fiber compact erbium-doped ring laser

A widely tunable narrow linewidth compact erbium-doped all-fiber ring laser with 104 nm tuning range was reported. An all-fiber Fabry-Perot filter (FFP-TF) was used to realize the laser tuning output, and the wavelength at constant voltage had high time stability. With the 8 m length erbium-doped fiber as gain medium, we realized widely tunable laser from 1513 to 1617 nm with the linewidth less than 40 pm at any wavelength. Pumped by the 976 nm laser diode, the fiber laser worked with slope efficiency of above 10% and threshold of less than 21 mW.     

全光纤多模速度干涉仪的研究

针对传统全光纤单模速度干涉仪在爆炸冲击试验中,前端的单模准直器对高速运动的物体的漫反射光难以有效收集,提出了全光纤多模速度干涉仪的装置。利用超辐射发光二极管作为光源,初步验证了全光纤多模速度干涉仪的可行性。主要阐述了全光纤多模速度干涉仪的原理和结构,并将其与全光纤单模速度干涉仪在喇叭振动速度的实验中进行比较,取得了一致的结果,最后还进行霍普金森压杆撞击实验,实测的速度最大值为10.49 m/s,与理论值10 m/s符合较好。     

全光纤光反馈环形腔结构多路激光被动相干合成

提出了基于全光纤光反馈环形腔结构的多路光纤激光相干合成方案,实现了多路激光的被动相干合成。全光纤结构避免了传统孔径拼接输出结构的旁斑能量耗散问题,保证了合成光束的光束质量。开展了实验研究,实现了4路光纤激光的相干锁相输出,获得时域、空域特性均十分稳定的合成光束,合成效率为96.1%,取得较好的合成效果。     

50 fs输出的全光纤展宽脉冲激光器

利用非线性偏振旋转锁模方法并引进激光谐振腔色散管理,在1550 nm波段上用展宽脉冲全光纤激光器直接产生50 fs无波分裂的高能量脉冲输出.在330 mW的抽运功率下平均输出功率为56.4 mW,单脉冲能量达到1.5 nJ.因为是全光纤结构,激光器的转换效率高达17%.输出光谱平滑,无任何边带存在,激光器处于无波分裂的单脉冲输出状态.     

175-W continuous-wave master oscillator power amplifier structure ytterbium-doped all-fiber laser

We report on hundred watts range ytterbium-doped all-fiber laser assembly based on the master oscillator power amplifier structure. It consisted of an oscillator and an amplifier with all-fiber components. And fiber fusion splice made the laser be an integrated fiber system. It generated up to 175.5 W of continuouswave (CW) output power at 1085 nm with more than 75% extraction efficiency in the amplifier when the total coupled pump power into the double clad fiber was 270 W.     

22 GHz窄线宽全光纤激光器实现2.62 kW近衍射极限输出

基于大模场面积掺镱光纤搭建了全光纤1064 nm高功率窄线宽光纤激光主振荡功率放大系统,实现了2625 W的最高功率输出,斜率效率76%。最高输出功率时,光束质量为Mx2=1.273,My2=1.255,3 dB光谱宽度为21.7 GHz,这是目前全光纤激光器在该光谱线宽下实现的最高输出功率。     

All-fiber passively mode-locked laser oscillator at 1.5 microm with watts-level average output power and high repetition rate

We report on a passively mode-locked all-fiber laser oscillator at 1.5 microm based on heavily doped phosphate-glass active fiber. An active fiber only 20 cm long is sufficient to produce as much as 2.4 W of average output power directly from the oscillator. The width of the mode-locked pulses varies from 8 ps at the lowest output power in the mode-locked state to 44 ps at the highest power. Our picosecond laser oscillator features a high repetition rate of 95 MHz and high peak pulse power of approximately 540 W. The oscillator combines the convenience of all-fiber construction with power performance that was previously achievable only with mode-locked bulk-optic laser oscillators or more complex systems involving fiber amplifiers.     

All-fiber single polarized Yb-doped fiber laser with a high extinction ratio

We present an all-fiber design for a single polarization Yb-doped fiber laser with all-fiber connections spliced. Single polarization with a high extinction ratio was achieved by the design of a laser cavity consisting of a fiber Bragg grating inscribed on a single-polarization fiber as a high reflective mirror and a piece of end-cleaved single-polarization fiber as an output coupler. The fiber laser operates at 1063.25 nm with an output power of 1.7 W, an optical signal- to-noise ratio of 70 dB and a narrow bandwidth of 54 pm. The laser output has a polarization extinction ratio of 700:1 or 28 dB, and a very stable power output.     

High-energy dissipative soliton with MHz repetition rate from an all-fiber passively mode-locked laser

We experimentally demonstrate pulse energy enhancement in an all-fiber passively mode-locked laser operating in the large normal dispersion regime. By increasing the laser cavity length as well as its net cavity dispersion, the proposed laser, which is mode-locked by nonlinear polarization rotation, generates highly chirped dissipative solitons with pulse energies up to 9.4 nJ. The fundamental repetition rate is 2.3 MHz, and the pulse duration is 35 ps. Such low repetition rate as well as wide pulse width makes this mode-locked all-fiber laser a suitable oscillator to directly seed a fiber amplifier, which can be used as compact sources for high-power applications.     

Soliton squeezing at the gigahertz rate in a Sagnac loop

We demonstrate what is to our knowledge the first all-fiber squeezing experiment. A balanced Sagnac loop is used, and a record 6.1+/-0.2dB of noise reduction below shot noise has been obtained without stabilization. A gigahertz Er-doped fiber laser and a high-power double-clad Er-Yb amplifier have been developed to suppress guided acoustic-wave Brillouin scattering and to make possible the all-fiber configuration.     

kW级全光纤激光器理论与实验研究

基于主振荡功率放大结构设计了kW级全光纤激光器,对激光器的功率分布及输出、弯曲选模以及冷却条件下增益光纤的热分布进行了数值模拟分析。搭建了所设计的全光纤激光器,在注入总泵浦功率1436W时,实验获得了1060W高功率连续激光输出,光光转换效率73.8%,光束质量因子小于1.6。初步分析了导致激光器实验输出与理论设计二者偏差的原因。