共查询到20条相似文献,搜索用时 125 毫秒
1.
2.
3.
针对多芯光纤完善了描述抽运光、信号光和Stokes信号的速率方程组.考虑了温差对受激布里渊散射的影响,利用有限元法求解温度分布方程组,分析了前向和后向抽运方式、对流系数、Stokes初始功率、光纤掺杂粒子密度和光纤长度对受激布里渊散射增益的影响.研究表明:后向抽运方式在抑制受激布里渊散射方面具有明显优势;减小对流系数有助于抑制受激布里渊散射;提高光纤掺杂密度能够加强抑制受激布里渊散射,同时也有助于提高光纤放大器的斜率效率.比较了在相同最佳光纤长度条件下,单芯和19芯光纤放大器的最高工作温度和受激布里渊散射
关键词:
光纤放大器
受激布里渊散射
大功率
有限元法 相似文献
4.
5.
S波段光纤拉曼放大器中级联受激布里渊散射串扰的实验研究 总被引:2,自引:0,他引:2
研究了光纤激光器前向抽运的S波段分布式光纤拉曼放大器中级联的受激布里渊散射(SBS)串扰现象。用窄光谱带宽(<100MHz)的可调谐激光二极管作为信号源,通过S波段分布式光纤拉曼放大器,当被放大的信号功率超过单模光纤受激布里渊散射的阈值时,出现了前向受激布里渊散射,这是传导声波布里渊散射在光纤放大器中放大的现象。随着拉曼放大器抽运功率的提高,在斯托克斯区,出现了两阶受激布里渊散射线,在实验中观测到偶数阶的受激布里渊散射谱线功率大于奇数阶的布里渊一瑞利散射线。当进一步增加拉曼放大器的抽运功率,出现了前向级联的多阶受激布里渊散射现象,拉曼放大器的增益下降,被放大的信号功率转换为受激布里渊散射,噪声变大。受激布里渊散射的串扰破坏了拉曼放大器的特性,使拉曼放大器无法在密集波分复用光纤传输系统中使用,因此需要严格地控制入纤的信号功率和放大器的抽运功率。在实验中还观测到在光纤拉曼放大器中被放大的信号光和受激布里渊散射线两侧的伴线。 相似文献
6.
光纤耦合半导体激光器(LD)泵浦的光纤激光放大器具有体积小、功质比高、稳定性好等优点,在工业加工和军事国防等诸多领域都有着广泛且重要的应用。然而,受限于器件制作工艺水平及光纤中的受激拉曼效应和模式不稳定效应,LD泵浦的光纤激光放大器难以同时实现高功率及高亮度激光输出。为实现更高功率、更高亮度的光纤激光输出,需要结合现有的器件工艺水平并同时实现对放大器中的受激拉曼散射效应和模式不稳定效应的有效抑制。报道了基于单位自研大模场增益光纤成功实现13 kW功率、高光束质量激光输出。激光器采用主振荡功率放大结构,放大级采用单后向981 nm泵浦自研大模场增益光纤,在总泵浦功率为15 kW时,输出功率达到12.94 kW,光束质量M2因子约为2.85。通过进一步优化器件性能及光纤模式控制,有望实现更高功率、更高亮度的光纤激光输出。 相似文献
7.
8.
光纤参变放大器光纤长度的优化设计 总被引:1,自引:1,他引:0
随着高输出功率掺铒光纤放大器和高非线性光纤的出现和使用,光纤参变放大器(OPAs)中出现了越来越多的增益饱和现象,这是光放大器中应该尽量避免的。对此,提出了依据光纤参变放大器的光纤非线性系数、抽运光功率、信号输入功率等参量对光纤长度进行优化设计的解决思路。明确提出最佳光纤长度的概念,即在其他参量一定的情况下使信号增益或信号输出功率达到最大所需的最小光纤长度,而且最佳光纤长度有利于提高光纤参变放大的增益带宽和波长转换带宽。通过数值积分求解描述光纤参变放大过程的非线性耦合方程,并运用控制变量法深入研究了最佳光纤长度与光纤非线性系数、抽运光功率、信号输入功率的关系。最后用最小二乘法进行数据拟合确定系数,得到简洁、实用的最佳光纤长度解析表达式。与已有实验结果比较表明,该解析式可很好地用来计算和优化光纤参变放大的光纤长度。 相似文献
9.
微纳光纤的端面反射特性是影响其传输特性及实际应用的重要因素之一. 本文提出了一种基于光环形器的微纳光纤端面反射特性测量方法. 该方法克服了3 dB耦合器直接测量法的不足, 通过引入气凝胶固定和功率补偿, 可有效地消除微纳光纤尾纤飘摆、光源输出不稳定及其内部损耗等不利因素, 从而提高测量的准确度. 采用该方案实验测量了微纳光纤的端面反射率及其与 光纤直径和传输波长间的关系. 实验结果与数值模拟结果相符, 表明该方法可有效地用于微纳光纤端面反射率测量及其与各特性参数之间关系的分析, 这对于微纳光纤激光器、放大器、耦合器及滤波器等光学微型器件的设计制作具有重要意义.
关键词:
光纤光学
微纳光纤
端面反射
光环形器 相似文献
10.
11.
以七芯光纤激光器为例,提出一种提高多芯光纤激光器总输出光功率中共相位模式所占比例的方法,即把多芯光纤激光器作为种子光源,输出信号光再经过多芯光纤放大器进行放大。基于速率方程组对激光器和放大器中的模式竞争进行了数值分析。计算表明:激光器输出端与放大器输入端之间距离存在一个最佳值,以使得放大器输出信号中低阶模式功率占总输出功率的比例最低,可以下降到小于1%。研究表明:级联放大系统可以有效增强共相位模式同时抑制低阶模式,比传统的塔耳博特腔激光器具有更好的光束质量。 相似文献
12.
A global design of an erbium-doped fiber and an open-loop erbium-doped fiber amplifier (EDFA) in a steady-state operation is discussed by applying genetic algorithms. Taking a signal gain and a bandwidth as objective functions, 7 parameters of the EDFA (erbium concentration, core radius, erbium-doped radius, refractive index difference, fiber length, pumping wavelength and signal power) are optimized by solving optical propagation equations, assuming a homogenous two-level active medium and a single-mode propagation. There is evidence to show that the 1480 nm pump utilized in usual EDFAs is not an optimal choice, which should be chosen around 1460 nm. The optimal core radius ranges 0.465–0.548 μm on pumping power 50–200 mW. Under different design objects and with different pumping powers, however, there are different optimal Er-doped concentrations, reflective index differences and fiber lengths. As a single fiber EDFA, 35 dB signal gain or 35 nm bandwidth is obtained with the 7 optimal parameters, 100 mW pumping power and 0.001 mW input signal power. 相似文献
13.
14.
Haijuan Chen Xianglin Yang 《International Journal of Infrared and Millimeter Waves》1997,18(9):1791-1797
A twin-core erbium-doped fiber amplifier has been studied. We establish the theoretical model, propose the coupled-propagation
equations, and then numerically simulate the characteristics of the amplifier. It is found that twin-core erbium-doped fiber
amplifier can provide different gains for signals with different input powers and self-heal the extra channel loss between
amplifying stages, thus equalizes the output signal level. The twin-core erbium-doped fiber amplifier is very suitable for
the future wavelength-division-multiplexed and optical frequency-division-multiplexed fiber networks. 相似文献
15.
Sun Hyok Chang Jin Soo Han Hee Sang Chung Kwangjoon Kim Je Soo Ko 《Optics Communications》2006,261(2):269-275
The characteristics of hybrid fiber amplifier (HFA) are investigated. HFA is composed of three stages: short-length EDFA pre-stage, DCF Raman amplifier, and power boosting EDFA. HFA has low noise figure, high output power, and also wide input power dynamic range. Gain control method of HFA is presented experimentally, and the transient gain excursion is suppressed to less than 0.5 dB at 3 dB channel add-drop. HFA can be used as line amplifier in optical transmission link even combined with distributed Raman amplifier due to wide input power dynamic range. The transmission performance of HFA is better than EDFA by more than 1.0 dB of Q-factor in 720 km SMF transmission. 相似文献
16.
In this paper, we propose and demonstrate a simple erbium amplifier module based on an erbium-doped fiber amplifier (EDFA) and an erbium-doped waveguide amplifier (EDWA) in serial, having gain-flatted (GF) and gain-clamped (GC) functions simultaneously. In first proposed GF amplifier scheme, the maximum gain variation of 2.5 dB can be observed in the effective range of 1528 to 1562 nm and the entire gains are above 35 dB with the input signal power of ?30 dBm. Hence, we investigate second scheme by optical feedback method in the proposed fiber amplifier achieving gain-flattened (GF) and gain-clamped (GC) efficiencies simultaneously. Thus, the maximum gain variations of ±0.8 and ±1.8 dB can be obtained in the operating range of 1530 to 1564 nm, when the input signal powers are ?16 and ?40 dBm, respectively. Moreover, the dynamic gain profile can be adjusted and dynamic input power range is also measured based on the proposed GF and GC fiber amplifier. 相似文献
17.
从双包层光纤激光器的速率方程出发,得到了光纤中泵浦光与激光的功率分布、输出功率与泵浦功率的关系、腔镜反射率及光纤长度对输出功率的影响。研究结果表明:输出激光功率与光纤长度及后腔镜反射率有很强的依赖关系,存在一个输出功率最大的最佳光纤长度。后腔镜反射率越大,输出激光功率越小;当光纤长度较短时,在输出端放置反射镜使泵浦光高反射,可以提高输出功率和效率。通过对端面泵浦掺Yb3+双包层光纤激光器进行理论分析和实验研究,得到输出激光的中心波长为1088.3nm,斜率效率为33.7%,最大输出功率为1.75W。 相似文献
18.
A novel gain-clamped long wavelength band (L-band) erbium-doped fiber amplifier (EDFA) is proposedand experimented by using a fiber Bragg grating (FBG) at the input end of the amplifier. This designprovides a good gain clamping and decreases noise effectively. It uses two sections of erbium-doped fiber(EDF) pumped by a 1480-nm laser diode (LD) for higher efficiency and lower noise figure (NF). The gainis clamped at 23 dB with a variation of 0.5 dB from input signal power of -30 to -8 dBm for 1589 nm andNF below 5 dB is obtained. At the longer wavelength in L-band higher gain is also obtained and the gainis clamped at 16 dB for 1614 nm effectively. Because the FBG injects a portion of backward amplifiedspontaneous emission (ASE) back into the system, the gain enhances 5 dB with inputting small signal. 相似文献
19.
在MCVD车床上利用“湿法”掺杂方法研制出纤芯高掺Ge的石英基掺Tm3+光纤预制棒,采用侧面研磨和抛光工艺制成横截面为正六边形的光纤预制棒.经拉丝,内层涂覆低折射率材料后制成包层抽运光纤.测试其吸收谱,并对光纤参数进行优化.通过在光纤两端紫外写入光纤Bragg光栅,制成线形光学谐振腔,在工作波长793nm的激光抽运下,获得工作波长1947.1031nm、功率2.05W的激光输出.由此证明这种光纤具有优异的光学特性.
关键词:
3+光纤')" href="#">石英基掺Tm3+光纤
光纤Bragg光栅
包层抽运
光纤激光器 相似文献
20.
Under small signal situation, the analytical expression for describing the output signal emitted from an Yb3+-doped fiber amplifier with a Gaussian input pulse signal is deduced, by full considering both fiber guided modes’ propagation constant and filling factor, which depend on the signal frequency. Pumped by continue wave (CW) source, the analytical expressions of the small signal gain and each guided mode's output power are obtained. Based on these analytical expressions, the various intensity distributions of output pulses amplified by the fiber amplifier with different Gaussian input pulse widths are analyzed. 相似文献