Demonstration of multi-Watt all-fiber superfluorescent source operating near 980 nm

The superfluorescent Yb-doped fiber source operating near 980 nm is studied. The design requirement is theoretically discussed aiming to suppress the amplified spontaneous emission around 1030 nm in the 980-nm superfluorescent fiber source. Based on the theoretical study, a multi-Watt, all-fiber, bi-directional, pumped, superfluorescent source operating near 980 nm is designed and experimentally demonstrated for the first time, to the best of our knowledge. The recorded 8.38-W combined output power is obtained with a 3-dB bandwidth about 3.5 nm. The power scaling of the 980-nm superfluorescent fiber source is limited by the parasitic laser oscillation.     

High-power diode-pumped Yb-doped fiber laser at 1150 nm

A model of steady-state rate equations including amplified spontaneous emission for long-wavelength Yb doped fiber laser is set up, which provides design principle for a practical laser system. We demonstrate a diode-pumped all-fiber Yb-doped fiber laser at 1150 nm with an output power of 33.6 W, the optical efficiency is 60%.     

激光二极管端面抽运Nd:YVO4实现1386 nm连续波激光输出

在Nd:YVO4晶体的4F3/2-4I13/2跃迁带内,除了1342 nm激光辐射之外,其它的跃迁谱线由于小的受激发射截面和强的寄生振荡,很难形成激光振荡.通过调整谐振腔损耗,获得了光纤耦合激光二极管端面抽运1386 nmNd:YVO4激光器激光连续输出.在抽运功率达到4.24 W时,得到了305 mW的1386 nm激光连续输出,最高输出功率下的斜效率为13.9%.实验中还观察到了1342 nm和1386 nm的双波长运转.根据抽运阈值能量和实验数据,计算得到了Nd:YVO4晶体中1386 nm激光辐射处的受激发射截面大约为(3±1)×10-19cm2.     

窄线宽光纤激光器在1030 nm波段实现3 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1030 nm高功率窄线宽光纤激光主振荡功率放大系统,实现了3004 W的最高功率输出,斜率效率69.27%,是目前报道的输出功率最高的1030 nm波段近衍射极限光纤激光器。最高输出功率时,x,y方向的光束质量因子分别为1.169,1.174,3 dB光谱宽度为0.18 nm,放大自发辐射抑制比达到37 dB。     

国产泵浦增益一体化复合功能激光光纤实现8.74 kW激光输出

正高功率光纤激光器一般采用信号光与MOPA放大级的"1+1"型串联结构,而第二级的MOPA放大结构通常存在两种结构方式:其一是短距离集中式端面泵浦方式,包括正向端泵和反向端泵,后者具有一定的技术优势,有利于实现窄线宽激光输出;其二是长距离分布式侧面泵浦方式,其工作原理是基于倏逝波耦合效应来实现数十米长度的长程侧面耦合,其典型代表是泵浦增益一体化复合功能激光光纤(又被称为"GT-wave光     

An Efficient Single-Frequency Yb-Doped All-Fiber MOPA Laser at 1064.3 nm

An efficient narrow-linewidth single-frequency(SF) Yb-doped all-fiber master oscillator power amplifier(MOPA)laser operating at 1064.3 nm is demonstrated experimentally.A ring cavity SF fiber laser is used as the seed source for the MOPA system and the Yb-doped fibers are employed as the gain medium or the saturable absorber.The SF operation is observed to be stable without mode hopping.The highest output power of 266 mW is obtained under the 400 mW pump power with the corresponding slope efficiency of 66.2%.The linewidth of the amplified output laser is approximately 1 kHz and its optical signal-to-noise ratio is over 45 dB.     

L波段线型腔波长可调谐掺铒光纤激光器

报道了工作波长在L波段的由两个光纤环境构成线型谐振腔的掺铒光纤激光器，通过调整环境中偏振控制器的状态来改变环境对不同波长的反射率以实现某些波长的激光输出。线型腔内的激光工作介质为两段不同掺杂浓度的掺铒光纤，其中一段铒光纤由一980nm激光器抽运，其产生的放大自发辐射谱在腔内再同时对两段掺铒光纤进行抽运，使它们的增益谱移位到L波段。实验中观察到了波长从1566．4nm到1592.4nm范围内可调的稳定的连续激光输出，其波长调谐范围达26nm。     

307 W high-power 1018 nm monolithic tandem pump fiber source with effective thermal management

We report a 307 W 1018 nm Yb-doped fiber laser pumped by a single 976 nm laser diode. The cavity slope efficiency is up to 75.9% and the amplified spontaneous emission is suppressed by 54 dB. The beam quality of the output laser has an M2 factor of 1.17. Effective thermal management is considered to ensure the stable operation of our system. The power stability at the maximum output power level is measured during a period of0.5 h and the power fluctuation is less than 0.8%. This architecture can be an effective high brightness pump source of core-pumping high-power fiber amplifiers.     

包层泵浦的L波段Er3+/Yb3+共掺光纤激光器

报道了一种工作波长在L波段的包层泵浦Er³⁺/Yb³⁺共掺光纤环形激光器. 环形腔内的激光工作介质为一段9 m长的Er³⁺/Yb³⁺共掺高掺杂光纤. 利用6个976 nm LD同时抽运前段Er³⁺/Yb³⁺共掺双包层光纤产生的放大自发辐射谱作二次抽运源, 使腔内增义谱由C波段移到L波段, 实现了L波段光纤激光器的稳定输出; 采用包层泵浦技术, 在抽运功率为3594.5 mW时, 测得泵浦入纤功率为2731.8 mW, 实现了输出连续功率最大518.4 mW,斜率效率达到19% 的激光输出; 所形成激光的工作波长为1613.94 nm, 激光光谱的3 dB带宽为1.5 nm, 边模抑制比接近于50 dB.     

L波段可调谐线形腔Er/Yb共掺双包层光纤激光器

报道了一种结构简单、工作在L波段、可调谐的线形腔Er/Yb共掺双包层光纤激光器.利用由两段高双折射光纤和两个偏振控制器构成的环镜滤波器对激光器进行调谐，使调谐范围达到34 nm，功率起伏小于±0.2 dB.用976 nm多模LD泵浦Er/Yb共掺双包层光纤产生的ASE作为二次泵源，对未泵浦的一段光纤进行泵浦，使腔内Er/Yb共掺光纤的增益谱移到L波段;多个泵浦源同时对Er/Yb共掺双包层光纤进行侧向泵浦，使激光器输出功率超过了200 mW.     

Wavelength tunable linear cavity cladding pump Er<Superscript>3+</Superscript>/Yb<Superscript>3+</Superscript>co-doped fiber laser operating in L-band

We have demonstrated a novel tunable linear cavity Er³⁺/Yb³⁺ co-doped fiber laser, which utilizes amplified spontaneous emission as a secondary pump source so that it can operate in L-band. The tuning wavelength range can be up to 34 nm, from 1588.6 to 1622.6 nm, and the output power excursion of the laser at different wavelengths can be less than 0.4 dB by using a two sections of high-birefringence fiber loop mirror as the wavelength filter. The high output power of 200 mW is realized by using the cladding-pump.     

Output Characteristics of High-Power Continuous Wave Raman Fiber Laser at 1484 nm Using Phosphosilicate Fiber

A continuous wave (CW) high-power Raman fiber laser (RFL) with maximum output power of 2.24 W and slope efficiency of 32.8% at 1484 nm is obtained using a CW 8.4 W/ 1064 nm Yb-doped double-clad fiber laser as a pump, 700 m phosphosilicate fiber, and cascaded cavities with two pairs of fiber Bragg grating mirrors for the first and the second Stokes orders. Theoretical simulation of the RFL using a very efficient and rapidly converging collocation method is done to understand and optimize the fiber length to obtain maximum second Stokes power. RFL performance for the 300, 700 and 1150 m phosphosilicate fiber lengths was experimentally investigated by observing maximum output power, slope efficiency, threshold power, and full-width at half maximum at the second Stokes wavelength.     

Efficient yellow-light generation by frequency doubling a narrow-linewidth 1150 nm ytterbium fiber oscillator

A linearly polarized, narrow-linewidth, diode-pumped, Yb-doped silica-fiber oscillator operating at 1150 nm was frequency doubled to produce 40 mW of 575 nm radiation. The oscillator generated 89 mW of cw linearly polarized output power and was tunable over 0.80 nm. The laser output was coupled to a periodically poled LiNbO3 waveguide that converted 67% of the coupled power to the yellow. The system was fully integrated, with no free-space optics, and had an overall optical-to-optical efficiency of 7.0% with respect to the incident diode-laser pump power.     

980-nm all-fiber mode-locked Yb-doped phosphate fiber oscillator based on semiconductor saturable absorber mirror and its amplifier

A 980-nm semiconductor saturable absorber mirror(SESAM) mode-locked Yb-doped phosphate fiber laser is demonstrated by using an all-fiber linear cavity configuration. Two different kinds of cavity lengths are introduced into the oscillator to obtain a robust and stable mode-locked seed source. When the cavity length is chosen to be 6 m, the oscillator generates an average output power of 3.5 m W and a pulse width of 76.27 ps with a repetition rate of 17.08 MHz. As the cavity length is optimized to short, 4.4-m W maximum output power and 61.15-ps pulse width are produced at a repetition rate of 20.96 MHz. The output spectrum is centered at 980 nm with a narrow spectral bandwidth of 0.13 nm. In the experiment, no undesired amplified spontaneous emission(ASE) nor harmful oscillation around 1030 nm is observed. Moreover,through a two-stage all-fiber-integrated amplifier, an output power of 740 m W is generated with a pulse width of 200 ps.     

Bi(2)O(3)-based erbium-doped fiber laser with a tunable range over 130 nm

A Bi(2)O(3)-based erbium-doped fiber (BIEDF) ring laser with a 134 nm tunable range is demonstrated with only 0.2 m of BIEDF as a gain media. The widely tunable range corresponds to the broad amplified spontaneous emission spectrum obtained from BIEDF. The pump power dependence and BIEDF length dependence of fiber laser properties are investigated. The tunable range varies depending on both pump power and BIEDF lengths. A high optical signal-to-noise ratio of over 70 dB for a 120 nm tunable range is also shown.     

122-W high-power single-frequency MOPA fiber laser in all-fiber format

We demonstrate a high-power single-frequency master oscillator power amplifier (MOPA) fiber laser.The central wavelength of the single-frequency fiber laser seed is 1 063.8 nm,with a linewidth narrower than 20 kHz and output power of 120 mW.By using two-stage amplification,a single-frequency fiber laser with an output power of 122 W is obtained,and the optical-optical conversion efficiency is 72%.No significant amplified spontaneous emission (ASE) or stimulated Brillouin scattering (SBS) is observed.The output power can be further increased by launching more pump power.     

1064nm超短腔DBR单频掺镱硅酸盐光纤激光器

提出了一种基于高掺杂硅酸盐增益光纤、输出波长为1 064nm的超短腔单频光纤激光器.该单频光纤激光器采用分布布拉格反射式腔型结构,有效腔长为2cm,其增益介质为1.1cm长的高浓度掺Yb3+光纤.通过恰当的温度控制,获得了线宽为4.8kHz的稳定单频激光输出.当注入泵浦光为378mW时,输出功率为13mW,斜效率为3.4%.在频率大于1 MHz时,测得该光纤激光器的相对噪声强度值约为-132dB/Hz.采用主振荡功率放大结构,对该单频光纤激光器的输出功率进行放大.当放大增益光纤长度选取为56cm时,得到了325mW的最大输出功率,其斜效率为52.8%.     

Simultaneous Double-Color Continuous Wave Raman Fiber Laser at 1239 nm and 1484 nm Using Phosphosilicate Fiber

Simultaneous double-color high-power continuous wave (CW) Raman fiber laser at 1239 nm and 1484 nm is demonstrated which uses CW 8.4 W Yb-doped double-clad fiber laser at 1064 nm as a pump, 1 km phosphosilicate fiber, and cascaded cavities consisting of two pairs of fiber Bragg grating (FBG) mirrors. Maximum output powers are 0.65 W at 1239 nm and 0.97 W at 1484 nm with a 50%/50% output mirror reflectivity pair, and 0.37 W at 1239 nm and 1.06 W at 1484 nm with a 75.5%/50% pair. The output characteristics of this laser for different FBG mirror reflectivities are reported.     

输出功率稳定的二级喇曼光纤激光器特性

提出一种输出功率稳定的二级喇曼光纤激光器,从理论分析角度探讨了它的特性.结果表明：由于在抽运光的二级斯托克斯光频附近的自发辐射光的钳制作用,激光器的一级和二级输出功率几乎都不受抽运功率波动的影响,从而降低了抽运光低频相对强度噪音转移|激光器输出的一级和二级斯托克斯光功率都很稳定,并且通过调节激光器结构中的可变衰减器,可以有效控制一级、二级激光的输出功率以及它们的比值.这些特性表明该喇曼光纤激光器很适合于作为喇曼光纤放大器的抽运源.     

Linearly polarized, 3.35 W narrow-linewidth, 1150 nm fiber master oscillator power amplifier for frequency doubling to the yellow

A high-power linearly polarized Yb-doped silica fiber master oscillator power amplifier at 1150 nm is reported. It produced 3.35 W cw and 2.33 W of average power in 1 micros pulses at a 100 kHz repetition rate, both with 8 pm linewidth. This is the first report, to the best of our knowledge, of a high-power Yb-doped fiber amplifier at a wavelength longer than 1135 nm. The pulsed output was frequency doubled in a bulk periodically poled near-stoichiometric LiTaO(3) chip to generate 976 mW of average power at 575 nm with an overall system optical-to-optical efficiency of 9.8% with respect to launched pump power.