共查询到20条相似文献,搜索用时 12 毫秒
1.
A simple set searching optimization algorithm is proposed for Er3+-Yb3+ co-doped fiber lasers in this paper. This method enables fiber lasers to acquire the optimum fiber length and Yb3+-Er3+ concentration ratio for a given accuracy. The numerical results illustrate that the optimum Yb3+-Er3+ concentration ratio changes very little, the optimum fiber length shortens and the corresponding output power is increased
with erbium ions concentration increasing. The total Yb3+ and Er3+ contents are nearly constant under certain pump power, while the optimum total erbium ions and ytterbium ions are decreased
with pump power decreasing. 相似文献
2.
Continuous wave laser operations of silica-based Er3+-Yb3+ co-doped waveguides have been numerically analyzed by means of a finite-element method. The theoretical model, based on propagation-rate equations, describes uniform upconversion by a dipole-dipole interaction between Er3+ ions, and includes a pair-induced energy transfer process from Yb 3+-Er3+ Numerical results show that single-frequency operation with slope efficiency higher than 50% and threshold pump powers of few mW can be achieved in short and heavily doped waveguides equipped with input dielectric mirrors and output distributed Bragg reflectors 相似文献
3.
Barnes W.L. Poole S.B. Townsend J.E. Reekie L. Taylor D.J. Payne D.N. 《Lightwave Technology, Journal of》1989,7(10):1461-1465
Single-mode fiber lasers operating at ~1.57 μm are described. Output powers of >2 mW are reported for laser diode pumped operation. Direct comparison is made between fiber lasers using sensitized erbium (Er3+ and Yb3+) and erbium on its own. The performance of Er3+-Yb3+ fiber lasers is analyzed in more detail as a function of fiber length. Both CW and Q-switched operations are studied and the results obtained demonstrate that practical sources at 1.5 μm are available from diode pumped Er3+ -Yb3+ systems 相似文献
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A comprehensive numerical fiber amplifier model has been used to optimize Er3+-Yb3+ codoped active fiber for maximum gain and quantum conversion efficiency (QCE) at large signal operation. The optimum cutoff wavelength of the LP11 mode has been found to increase from 800 mm at low pump powers (≈50 mW) to 1400 mn at pump powers higher than 500 mW. While at low pump powers fibers with higher numerical aperture give higher QCE, at high pump levels better large signal performance is achieved with fibers having lower numerical aperture 相似文献
6.
Minelly J.D. Barnes W.L. Laming R.I. Morkel P.R. Townsend J.E. Grubb S.G. Payne D.N. 《Photonics Technology Letters, IEEE》1993,5(3):301-303
Single-mode double-clad Er3+/Yb3+ co-doped fibers are shown to be suitable for diode array pumping at around 960 nm. A fiber laser with 96-W output power at 1.53 μm and a power amplifier exhibiting a small signal gain of 24 dB and a saturated output power of +17 dBm are reported 相似文献
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有机发光材料可能对人体或环境造成影响,除此之外还有生产成本高、发光易淬灭、发光强度与颜色不易于控制的缺点,因此探索性能优越的稀土发光材料并寻找其应用价值是具有重要意义的。本文基于水热辅助固相法制备出Er3+、Eu3+离子共掺杂LaOF荧光粉,通过X射线衍射仪(X-ray diffractometer, XRD)、扫描电镜(scanning electron microscope, SEM)和荧光分析仪对不同Er3+掺杂浓度下的LaOF∶Eu3+荧光粉体的相组成、粒径尺寸、形貌及荧光光谱进行表征与分析。结果表明:在900℃的温度下煅烧,物相由前驱体LaF3转变为四方相LaOF,且随着Er3+掺杂浓度的升高,在365 nm与393 nm波长激发下均呈现出多色可调谐的发光特性,其中365 nm激发下呈现自橙色光向黄色光的转变,而在393 nm光辐射下则由橙色光向品红色光过渡。将Er3+、Eu3+共掺杂LaOF荧光粉制成... 相似文献
9.
Dos Santos P.V. De Araujo M.T. Gouveia-Neto A.S. Neto J.A.M. Sombra A.S.B. 《Quantum Electronics, IEEE Journal of》1999,35(3):395-399
Optical thermometry based upon infrared excited upconversion fluorescence emission in Er3+- and Er3+-Yb3+ - doped Ga2S3-La2O3 chalcogenide glasses excited at 1.54 and 1.06 μm, respectively, is presented. Temperature sensing in the region of 20°C-220°C with 0.3°C accuracy using excitation powers readily obtainable from commercially available semiconductor lasers was achieved. The temperature sensing approach is independent of fluctuations in excitation intensity and transmission and requires a simple and low-cost signal detection and processing system. The results also indicate that the glassy host material plays a major role in the performance of the sensing system 相似文献
10.
Vienne G.G. Caplen J.E. Liang Dong Minelly J.D. Nilsson J. Payne D.N. 《Lightwave Technology, Journal of》1998,16(11):1990-2001
Fabrication process of efficient Yb3+,Er3+ codoped phosphosilicate fibers by modified chemical vapor deposition (MCVD) combined with the solution doping technique is studied in detail. We show that the process can be adapted to incorporate low viscosity phosphate glass and some important issues in the fabrication process are discussed. These include the sensitive presintering pass. We also report on the fabrication of a low loss all-glass double clad Yb3+:Er3+ codoped fiber. We explain how we evaluate the fibers and discuss the effect of the ytterbium to erbium concentration ratio on the laser characteristics. Finally, we present results of some investigations into the mechanisms which can affect the efficiency of the lasers, and show that the detrimental up-conversion from the metastable level of the erbium ions is dramatically reduced by the presence of the ytterbium ions 相似文献
11.
目前1.5m LD泵浦铒玻璃被动调Q微型激光器是军事激光测距的研究热点,获得较高的激光重复频率和单脉冲能量尤为重要。文中主要报道了一种应用于激光测距领域的铒镱共掺磷酸盐玻璃被动调Q微片激光器。激光器采用中心波长为940 nm的单管二极管为泵浦源,铒镱共掺磷酸盐玻璃(Er3+,Yb3+:glass)作为增益介质,CO2+:MgAl2O4(CO:MALO)作为可饱和吸收体。通过分析泵浦光斑半径对模式匹配影响,优化泵浦光斑半径,实验分析可饱和吸收体初始透过率T0和输出镜反射率R对输出激光参数影响,优化T0和R值。最终实验中采用增益预泵浦方式,实现重频1 kHz,单脉冲能量40 J,脉宽5.09 ns,峰值功率7.85 kW,光束质量M2=1.4,波长1 535 nm的稳定激光输出。 相似文献
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Short high-concentration Yb3+-sensitized Er3+-doped fiber amplifiers are modeled and numerically investigated in the small-signal domain. Concentration quenching is included with a term quadratic in the concentration of excited Er3+ . We find that for fibers shorter than 1 m, the small-signal gain can be larger for sensitized fibers than for non-sensitized ones (31 dB gain vs. 22 dB at 5 cm). Without concentration quenching (e.g. for long fibers), Yb3+-free amplifiers have a higher small-signal gain. The achievable gain of the sensitized amplifier is independent of the pump laser wavelength, if the Yb-concentration is correspondingly optimized. However, restrictions on allowable Yb-concentrations imply that for a specific pump wavelength, a finite range of amplifiers lengths is suitable 相似文献
14.
Hu Y. Jiang S. Luo T. Seneschal K. Morrell M. Smektala F. Honkanen S. Lucas J. Peyghambarian N. 《Photonics Technology Letters, IEEE》2001,13(7):657-659
Performance of high-concentration Er3+-Yb3+-codoped phosphate fiber amplifiers in a copumping configuration is presented. Gain, noise figure, and output signal saturation power of fiber amplifiers with different lengths are reported. From a 3.6-cm-long fiber, 18-dB internal gain, i.e., 5 dB/cm, for small signal input at 1535 nm, was achieved. To the best of our knowledge, this is the highest gain per unit length for erbium-doped fiber amplifiers ever reported 相似文献
15.
Loh W.H. Atkinson D. Morkel P.R. Hopkinson M. Rivers A. Seeds A.J. Payne D.N. 《Photonics Technology Letters, IEEE》1993,5(1):35-37
A nonlinear mirror consisting of an InGaAs/InP multiple-quantum-well saturable absorber integrated with a Bragg reflector stack has been used to passively mode-lock a fiber laser in an extremely simple and advantageous linear-cavity configuration. To date, pulses as short as 7.6 ps have been observed 相似文献
16.
The saturation of the 2.71 μm laser output has been measured in erbium-doped ZBLAN singlemode fibres with Er3+ concentrations of 1000, 5000 and 10000 ppm mol. Limits of the single-mode-laser output are discussed 相似文献
17.
In experimental and theoretical study of anomalous dispersion in Er3+and Er3+-Yb3+-doped fibers has been developed. Anomalous time delay caused by both absorption and emission at 1.535 μm has been theoretically calculated and experimentally measured. A pump power dependence of anomalous time delay in rare-earth-doped fibers has been theoretically calculated and experimentally investigated. It has been shown that pump power fluctuations lead to propagation time jitter in Er3+-doped fiber amplifiers. The pulse interaction due to refractive index change caused by gain saturation is predicted. It has been shown that for Er 3+-doped fibers with SiO2-GeO2 core composition, the anomalous dispersion per 1-dB gain is twice that of fibers with SiO2-Al2O3 core, which is caused by gain curve form difference. A scheme of mutual compensation of intrinsic fiber dispersion and anomalous dispersion caused by Er3+ in the region 1.532-1.537 μm has been suggested 相似文献
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The realization, the characteristics and the bit-error-rate (BER) performance of a single frequency, linear polarization Er3+-doped distributed Bragg reflector fiber laser are reported. The device, pumped at 980 nm, gives a maximum output power of 13 mW with an overall slope efficiency η=24%, a continuous-wave intensity ripple around 1% and a linewidth of 2.2 kHz. The BER test, performed without any polarization control system in a complete 475-km-long 2.5-Gb/s wavelength-division-multiplexed transmission line, shows only a 0.5-dB penalty is introduced 相似文献
20.
Upconversion lasing in Er:YAlO3 is reported. Laser emission was produced using both sequential two-step pumping and cross-relaxation energy transfer. In addition, photon avalanche upconversion pumping was demonstrated. Selection among these pumping mechanisms is determined by the pump wavelength, and laser operation was obtained with excitation between 785 nm and 840 nm. The highest laser output power was achieved at 34°K, where 918 mW of pump power at 807 nm produced 121 mW of TEM00 emission. The optical conversion efficiency was 13%. Repetitively Q-switched operation is reported, and the temporal- and temperature-dependence of the laser output is discussed 相似文献