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太阳光直接抽运激光器在空间光通信、遥感等领域有着重要的潜在应用,但是一直以来人们对太阳光抽运激光器的研究局限于以掺Nd3+粒子为增益介质的1μm波段.通过对现有固体激光工作物质的吸收谱进行分析,发现掺Tm3+离子在太阳辐射较强的可见光波段具有强的吸收峰,使2μm人眼安全波段实现太阳光直接抽运激光输出成为可能.本文对Tm:YAG和Tm:YAP两种常见晶体的吸收谱与太阳光谱匹配度进行了分析计算,得出两种材料用于太阳光抽运激光器的阈值抽运功率密度分别为1.14和1.434 kW/cm3.选择与抽运阈值功率密度低的Tm:YAG晶体作为增益介质,使用TracePro软件建立太阳光抽运激光器的二级抽运模型,并对模型进行优化,得到了锥形腔窗口与菲涅耳透镜的最佳距离、晶体棒的最佳长度以及锥形腔最佳锥度.本文的工作为实现太阳光直接抽运2μm激光输出做了理论上的准备. 相似文献
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研究了无内热激光器和激光放大器运转时对抽运光的需求条件.运用激光器的速率方程理论,给出了抽运光所应满足条件的表达式.无内热激光运转时,不仅要求抽运光光强要大于阈值条件,而且要大于某个最小抽运光强(与增益材料性质、抽运光波长、激光波长等有关).以掺镱的KY(WO4)2晶体为无内热激光器的放大介质,计算了抽运光光强应满足的空间分布条件.要使激光器无内热运转,抽运光光强需随激光光强的增大而相应减小.对于无内热激光器,抽运光光强的空间分布与谐振腔前后镜的反射率和增益介质长度密切相关,在谐振腔输出耦合镜反射率不是太低的情况下,腔内抽运光强需近似为均匀分布. 相似文献
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The absorption spectrum of a new crystal Nd : Sr5(PO4)3F or Nd : S-FAP, was measured, its two strong absorption peaks and broad effective absorption band showed that Nd : S-FAP can be appropriately pumped at 575 nm and 805.4 nm as well as with a xenon flashlamp. By using a tunable dye-laser (570.0~600.0 nm), a laser-diode (805 nm) and a xenon flash lamp as pump sources, respectively, the performance of a low threshold and high efficiency Nd:S-FAP laser at 1.059 (μm) (including pulse run, cw run, free-run and Q-switch run) has been demonstrated. The laser characteristics, such as the emission spectrum, the output energy, the output power, the pulse width, etc, were measured. In addition, the prospect of a Nd:S-FAP crystal for low-threshold high-efficiency miniature lasers is discussed. 相似文献
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The nitrogen laser pumped dye laser output has been studied with emphasis on the behaviour of amplified spontaneous emission
(ASE) with respect to the tuning wavelength, pump energy, dyes and their concentration and solvents. Spectral spread of ASE
is narrower than fluorescence and its maximum is shifted towards the red side. However, lasing occurs beyond the ASE region.
ASE is small at high gain wavelength and increases at the edges of the gain curve. Laser energy is highest at the ASE peak
with minimum ASE present in the output. ASE is reduced with increased laser energy in the energy transfer dye lasers. 相似文献
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In this article the operation of a composite Yb:YAG/YAG asymmetric hexagonal thin disk laser is optimized. This structure consists an Yb:YAG thin sheet as laser material and a diffusion bonded undoped material on top of thin sheet. Three diodes are placed outside the asymmetric hexagonal shape disk, and the emitting light is coupled via three lens ducts through its three edges and propagates through the disk along the zigzag path and repeatedly passes the gain medium, thus pump uniformity and absorption efficiency are improved. A Monte Carlo ray tracing code and Finite Element Analysis is utilized for calculation of absorbed pump density and volume temperature distribution and also thermal and mechanical stresses, respectively. Finally the output power is calculated. The triplet designing parameters, namely absorbed power efficiency, absorption uniformity and temperature distribution are optimized. Results show this edge-facet pumped geometry is a high efficient configuration for thin gain lasers. 相似文献
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We report the demonstration of a Cr:forsterite laser pumped by broad-area laser diodes producing non-diffraction-limited beams. The use of a thin crystal to reduce losses at the lasing wavelength and of short-wavelength pump diodes reduces the lasing threshold to <500mW .Relatively low output powers (5mW) are obtained, but prospects for increasing the power and achieving mode-locked operation of this laser are good and are discussed. 相似文献
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Optically pumped alkali vapor lasers are currently being developed in several laboratories. The objective is to construct high-powered lasers that also exhibit excellent beam quality. Considerable progress has been made, but there are technical challenges associated with the reactivity of the metal atoms. Rare gas atoms (Rg) excited to the np(5)(n+1)s (3)P(2) configuration are metastable and have spectral properties that are closely similar to those of the alkali metals. In principle, optically pumped lasers could be constructed using excitation of the np(5)(n+1)p←np(5)(n+1)s transitions. We have demonstrated this potential by observing gain and lasing for optically pumped Ar(*), Kr(*) and Xe(*). Three-level lasing schemes were used, with He or Ar as the collisional energy transfer agent that established the population inversion. These laser systems have the advantage of using inert reagents that are gases at room temperature. 相似文献
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This Letter presents a polarimetric study of the emission of random lasers from organic dyes. Coherent lasing modes from samples with ethanol solvent showed a high degree of polarization and did not influence each other in polarization. The proper choice of a laser dye with asymmetric absorption momenta, a highly viscous solvent, and a linear pump polarization can cause the random lasing emission to be completely linearly polarized for all wavelengths within the amplification range. 相似文献
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J. Chen H. Mizuno H. Kawano A. Miyawaki K. Midorikawa 《Applied physics. B, Lasers and optics》2006,85(1):45-48
We experimentally demonstrated two-photon pumping of random lasers using picosecond and nanosecond pump lasers. The picosecond laser pumping experiment was performed with 400 ps laser pulses at 770 nm, and the gain media was a Coumarin 480D dye solution doped with TiO2 nanoparticles. Onset of laser action was observed at a pump laser pulse energy below 500 μJ. The nanosecond laser pumping experiment was performed with 7 ns laser pulses at 1064 nm, and the gain media was a Rhodamine 640 dye solution doped with TiO2 nanoparticles. Onset of laser action was observed at a pump laser energy ∼18 mJ. Our results suggest that there exists an optimal pulse duration of the pumping laser in two-photon pumped random lasing that leads to minimum photodamage of the gain media and still keeps a high pumping efficiency. PACS 33.50.Dq; 42.55.Mv; 42.55.Zz 相似文献