共查询到20条相似文献,搜索用时 281 毫秒
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大功率脉冲TEA CO2激光器的放电腔在不同工作气压和不同配气比例条件下对激光器输出能量和电光转换效率均有较大影响,因此,通过充气压力从30kPa到60kPa的改变和配气比例CO2:N2=1:1到CO2:N2=1:4的变化,可以改变激光器的输出能量,提高激光器电光转换效率。实验结果表明:当CO2:N2的配气比例为1:3时,激光器输出的电光转换效率存在最佳点。在最佳配气比例CO2:N2:He=3:9:28,总气压40kPa和注入激励电能保持不变的情况下,激光器单脉冲放电时的输出能量为24.6J;激光器高重复频率放电运转时的电光转换效率达16.4%。激光器的最高放电频率可以达到500Hz并且连续稳定运行工作。 相似文献
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基于对海洋进行快速大面积探测或对潜通讯的需要.开始了对S2分子激光器的研制。S2分子激光器与其它几种激光器相比具有明显的优势.介绍了S2分子的获得方式、S2分子的势能曲线及特点、S2分子光谱特性等。经过反复论证及试验,取得了阶段性研究成果,为横向脉冲快放电小型S2分子激光器的研制及实现激光振荡奠定了坚实的基础。 相似文献
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辅助光对NaCl(OH-)和KCl(Na+,OH-)晶体中的类F2+型色心激光输出的影响 总被引:1,自引:1,他引:0
文中报进了有关辅助光对NaCl(OH-):(F2+)H及KCl(Na+,OH-):(F2+)AH色心激光输出功率影响的主要研究结果。初步探讨了辅助光作用的物理机制。 相似文献
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在3~20 GPa压力范围内,测量了含氧量较低的YBa2Cu3O7-δ(δ=0.46)单晶压力增强效应(dTc/dp=4.9KGPa-1);YBa2Cu3O7(Tc0=90 K)单晶在压力下临界电流密度随压力变化;外磁场H=30 kOe时,Tc与磁场、压力关系;压力达16.5 GPa下,Bi2Sr2CaCu2Ox单晶Tc(p)关系(dTc/dp=-0.4 KGPa-1)。发现Y系高温超导体的温度压力导数dTc/dp与Tc0中间呈dTc/dp=b-mTc0线性关系(b、m为常数)。结合压力下Y系超导体结构相变和含氧量对Tc影响,分析这类超导体Tc有很强的正压力效应的原因。把实验结果同几种超导电性微观理论模型进行了分析和比较。 相似文献
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本文对具有较大非线性系数,较快非线性响应和回复时间的CdSxSe1-x半导体微晶掺杂玻璃能否在挽共振环(亦称为非谐振环)APM激光器中有效地压缩脉宽等问题做了详尽的理论与实验的切耐与分析。理论计算与实验研究的结果均表明:在抗共振环APM激光器中,应用CdSxSe1-x半导体微晶掺杂玻璃不能使超短光脉冲宽度被压窄。 相似文献
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在传统光纤激光器工作原理的基础上,考虑光子晶体光纤(PCF)模场分布特征,给出了连续泵浦情况下单模PCF激光器的速率方程和功率传输方程。利用该方程对掺镱单模PCF激光器的性能进行了数值模拟研究。结果表明:虽然空气占空比大小对PCF激光器的输出功率、泵浦阈值和斜率效率等影响不显著,但对拉曼非线性阈值影响却很大。当泵浦功率小于拉曼非线性阈值时,激光器主要输出信号激光;当超过拉曼阈值且在较宽的范围内,激光器同时输出功率相近的信号激光和拉曼光。基于这种效应,提出一种由泵浦功率控制的双波长光纤激光器的新思路。考虑到PCF非线性系数的可调控特性,采用不同光纤有可能在较宽的功率范围获得双波长激光振荡。 相似文献
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Jianfeng Li Yu Chen Ming Chen Hao Chen Xuebi Jin Yi Yang Zhiyong Dai Yong Liu 《Optics Communications》2011,284(5):1278-1283
Based on the structure of mid-infrared chalcogenide fiber Raman laser, the nonlinear coupled equations and heat dissipation equations are constructed. The effects of laser parameters including pump power, fiber length, reflectance of output coupler and fiber loss coefficient on laser performance are numerically analyzed. The results show that the Raman laser pumped at 2 μm can operate at high slope efficiency using the optimized structure parameters. In addition, the output laser power decreases dramatically with the increasing of fiber loss coefficient. Moreover, the temperature distributions along the fiber radial and axial directions and the maximum temperature versus launched pump power are calculated according to the heat dissipation equations. The results show that the maximum temperature in the fiber increases dramatically with the increasing launched pump power, which is above 300 °C for launched pump power of 21 W. The above obtained results can be used for theoretical guiding and optimizing design of practical chalcogenide fiber Raman laser. 相似文献
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Impacts of operational parameters on nonlinear polarization rotation-based passively mode-locked fiber laser 下载免费PDF全文
The operational parameters including the polarization controlling and the pump power in a nonlinear polarization rotation-based passively mode-locked fiber laser are studied in this paper.The carrier rate equations of the activated erbium-doped fiber are first employed together with the nonlinear Shro¨dinger equations to reveal the relation between the operational parameters and the output state of the passively mode-locked fiber laser.The numerical and experimental results demonstrate that the output state of the mode-locked laser varies with the polarization controlling and the pump power.The periodicity of the polarization controlling is observed.With given pump power,there exists a set of polarization controlling under which the ultra-short pulse can be generated.With given polarization controlling,the mode-locked state can be maintained generally except for some particular values of pump power.Three shapes of the output optical spectra from the fiber cavity can be identified when the pump power changes.The results in this paper provide a comprehensive insight into the operation of the nonlinear polarization rotation-based passively mode-locked fiber laser. 相似文献
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本文介绍了一种用波长为809nm的激光二极管(LD)端面泵浦厚度为1mm的微片Nd:YVO4全固化固体激光器。器件结构上采用了一种独特的光学系统,该系统由分别用于LD激光束的耦合和聚焦的两部分组成。由Nd:YVO4的一个平面与一个曲率半径为21mm的球面镜组成半共焦腔,以获得高的转换效率。文中详细讨论了单横模运转时的泵浦光与激光腔模之间的匹配问题。当泵浦光功率为400mW时,获得152mW的1064nm波长的TEM00模激光输出。器件阈值功率为48.3mW,总的光-光转换效率为38%,斜效率为43%. 相似文献
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受激拉曼散射和热效应会限制光纤激光器功率的提高。利用高功率光纤激光器的速率方程和热传导方程,理论研究了双端泵浦和分布泵浦下双包层光纤激光器的受激拉曼散射和热效应,得到了光纤中的泵浦光、激光和斯托克斯光的功率分布,光纤激光器的输出特性以及光纤中的温度分布。分析表明,当泵浦功率增大到一定值时,光纤激光器中出现SRS,一部分激光功率会转移给斯托克斯光,影响激光功率进一步提高;与双端泵浦方式相比,分布泵浦下光纤激光器的斜率效率和最大输出功率相差不大,但是,光纤中的温度分布被有效地降低,因此,分布泵浦方式更为有效。 相似文献
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P. Mandel 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2000,8(3):431-442
The global integro-differential rate equations describing a multimode laser are analyzed. Expressions for the relaxation oscillation
frequencies and their damping rates in the single-mode and two-mode regimes are obtained without specifying either the cavity
geometry or the longitudinal pump profile. On the same level of generality, we prove the existence of universal relations
relating the peaks of the power spectra in the two-mode regime. For a Fabry-Perot with arbitrary longitudinal pump profile,
series expansions of all the physical functions are derived in powers of the pump moments. These moments are averages of the
pump profile over cavity modes at linear combinations of the lasing frequencies and their harmonics. These results apply to
end-pumped and/or partially filled lasers. For a single mode Fabry-Perot laser, we prove that the contribution to the steady
state intensity from the lasing mode varies from 75% close to the lasing threshold to zero at high intensity. The remainder
comes from the harmonics of the lasing mode. Analyzing the steady state single mode intensity equation in terms of the pump
gratings, we prove that close to the lasing threshold only the space average of the pump and its grating oscillating at twice
the lasing wave number do not vanish. This provides a hint towards the justification of the usual modal rate equations which
retain only these two functions in the dynamical evolution of a laser. For a Fabry-Perot with constant pump profile, an exact
expression for the upper boundary of the stable single mode regime is derived. In that two-mode regime, we prove that there
is a critical value of the pump at which the ratio of the two relaxation oscillation frequencies is 2, leading to an internal
resonance. 相似文献
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The effects of temperature on the output power and optimal conditions of Ytterbium-doped double-cladding fiber lasers (YDDFLs) are discussed. Temperature-dependent rate equations for YDDFLs based on Boltzmann distribution are built in two-end pump model. The results show that the output power and the slope efficiency decrease with the increase of temperature. The increase of pump power results in that the effect of the temperature on the output performance increases, and the fiber length is a factor that the effect of the temperature depends on really. Moreover we combine the heat distribution formula with the rate equations and compare the numerical results considering with that not considering the temperature-dependence inside laser cavity, the effect of temperature can be ignored only when the pump power is lower, and the optimal fiber length becomes longer when considering the temperature-dependence. 相似文献
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Jogy George Jolly Xavier P S.C. Mehendale Bhanu P. Singh T.P.S. Nathan 《Optics & Laser Technology》2007,39(6):1193-1198
In this paper, we present the study of the effect of axial mode spacing on the performance of a single longitudinal mode (SLM) laser in an end pumped solid-state laser system. We present a theoretical analysis of an SLM laser for arbitrary values of axial mode spacing, which predicts that the ratio of the maximum pump power up to which SLM operation is possible to the pump power at the lasing threshold is strongly dependent on the axial mode separation. We also present the results of a study where a temperature controlled birefringent filter was used to increase the axial mode spacing in a diode end pumped solid-state laser system, resulting in an enhancement of the SLM laser performance. 相似文献