Continuous-wave solid-state dye laser

We report the first realization of a cw solid-state dye laser. The laser medium consists of a laser dye (Rhodamine 6G) dissolved in a photopolymer. The UV-cured solution is sandwiched between two DVD substrates. The resonator design was derived from a conventional liquid solvent dye laser geometry. The laser radiation can be tuned from 565 to 615 nm by using a birefringent filter. A pump power of 2 W leads to a cw output power of more than 20 mW.     

中红外固体激光器研究进展

本文介绍了中红外固体激光器中新型的Fe²⁺: ZnSe激光器和基于MgO: PPLN、ZnGeP₂晶体的光参量振荡器的发展现状,讨论了它们在发展过程中遇到的技术难题,探讨了中红外固体激光器的未来发展方向。波长为3~5 μm的中红外固体激光器具有效率高、体积小和重量轻等优点,在工业、医疗、军事等方面具有重要应用价值,研制大尺寸、高质量中红外激光晶体和输出波长更长的红外高功率激光泵浦源已成为中红外固体激光器未来发展方向之一。     

Dispersive solid-state dye laser oscillators

Narrow-linewidth multiple-prism grating solid-state dye laser oscillators are analysed using ray transfer matrices. Attention is given to beam divergence measurements and the effect on them of thermal lensing, at the solid-state gain medium. It is found that although thermal lensing leads to an increment of beam divergence, it induces oscillation in the unstable resonator regime, thus contributing to the attainment of TEM00 beam profiles. In addition, narrow-linewidth emission in dispersive oscillators, incorporating rhodamine 6 G doped HEMA:MMA gain media, is reported for the first time. Laser efficiency is 4–5% at a laser linewidth ≤1.8 GHz for double-longitudinal-mode emission. Beam divergence is measured in the 2–2.3 mrad range, in good agreement with theory. This revised version was published online in November 2006 with corrections to the Cover Date.     

Wavelength-tunable organic solid-state distributed-feedback laser

We report on a wavelength-tunable organic solid-state laser based on a second-order distributed-feedback (DFB) resonator design with the guest–host system Alq₃:DCM2 as the gain medium. The laser wavelength can be shifted from 608.9 to 646.5 nm by varying the grating period of the Bragg reflector. This allows the characterization of laser parameters for a large wavelength region on a single sample. The laser threshold and output characteristics are measured for different laser wavelengths. A minimum threshold for laser activity occurs at a lasing wavelength of 633 nm, giving the spectral position of the gain maximum. PACS 42.70.Jk; 78.45.+h; 78.66.Qn     

High-power monolithic unstable-resonator solid-state laser

We report the operation of a diode-pumped monolithic Q-switched unstable-resonator solid-state laser that generates 2.15-mJ, 2-ns pulses in a single transverse mode and a single longitudinal mode. We show that the unstable resonator is effective in suppressing the spatial and the temporal instability of the laser beam in a disk-shaped laser whose transverse dimension is comparable with or larger than its longitudinal dimension.     

YAG固体激光器的时间延迟特性

在电光调Q激光装置上,设计了KD*P晶体电光效应验证实验,总结了简单易行的光路调整方法,测试和讨论了调Q延迟时间对激光器输出能量和脉宽的影响.结果表明,最佳延迟时间的设定可以提高激光器输出能量.     

Broadly tunable femtosecond solid-state laser sources

The techniques of coupled-cavity modelocking and self-modelocking in which intensity-induced nonlinear effects are exploited have been reviewed for broad-band gain media. Particular emphases have been placed upon the archetypical colour-centre and titanium-sapphire laser configurations in which these techniques were first demonstrated and subsequent refinements are set in context. A femtosecond optical parametric oscillator pumped by a self-mode-locked titanium-sapphire laser has also been described as an exemplar of a practical means of extending the source tunability into the mid-infrared spectral region.     

Towards a solid-state ring laser gyroscope

In this paper, we report our recent progress towards a solid-state ring laser gyroscope (RLG), where mode competition is circumvented by active control of differential losses, and nonlinear effects are mitigated by longitudinal vibration of the gain medium. The resulting dynamics is significantly different from that of a classical helium–neon RLG, owing in particular to parametric resonances that occur when the Sagnac frequency is an integer multiple of the crystal vibration frequency. We describe the main experimental and theoretical results obtained so far, and the prospects of practical applications in the near future.     

Laser output of radial-slab solid-state laser

In this letter, numerical simulation and experimental study of a radial-slab solid-state laser are presented. The laser includes four crossing-slabs pumped by four Xe flashlamps. The numerical simulation of coherent intensity in the near field and the far field indicates that the laser with the structure can improve the quality of output beam compared with incoherent beam combination. The radial-slab solid-state laser is fabricated, and initial experiments are carried out at a pulse repetition of 1 Hz. Nine beams in the near field and one combined beam in the far field are obtained in our initial experiment. The experimental results are consistent with the numerical analysis in the coherent condition. The results show that coherent beam combination is obtained by this laser.     

Multimode pumped continuous-wave solid-state Raman laser

We demonstrate the continuous-wave operation of a solid-state Raman laser containing a barium nitrate crystal as the Raman medium. The Raman laser, which has a singly resonant cavity, is pumped by multimode radiation. The Raman oscillation threshold is reached at approximately 2 W of pump power. As much as 500 kW/cm2 of Stokes power density at 60-kW/cm2 pump power density is obtained in the cavity.     

Chaos in a multimode solid-state laser system

When a nonlinear crystal is placed within a multimode solid-state laser cavity, deterministic fluctuations are induced in the output intensity. In this paper, the results of our studies of the intensity noise in a diode pumped, intracavity frequency doubled Nd:YAG (neodymium doped yttrium aluminum garnet) laser will be presented. First, a novel technique to eliminate these fluctuations is described. Second, the observation of antiphase states in the laser output is discussed. These states are characterized by a cyclic periodic pulsing of the individual longitudinal mode intensities. Finally, the statistical properties of chaotic intensity fluctuations are characterized. It is be demonstrated that it is possible to accurately model the laser dynamics by a system of globally coupled, nonlinear oscillators.     

一种LD泵浦双向输出固体环形激光器

提出了一种用于激光陀螺仪的LD泵浦Nd∶YVO4双向输出固体环形激光器。计算了谐振腔的环绕矩阵,分析了曲面镜焦距和放置距离对谐振腔稳定性的影响。得出了构成环形腔的稳定条件,光腰最大化条件,以及光束特性。并对所设计的环形腔进行了实验,获得了双向、多纵模基横模连续输出。     

高功率固体激光器喷雾冷却技术

喷雾冷却作为一种解决高功率激光器散热需求的技术得到越来越多的关注。结合近几年的研究工作,综述了喷雾冷却技术的研究现状。针对高功率激光器的散热需求,主要从传热机理、影响因素、温度均匀性方面进行阐述,分析了存在的问题。提出将制冷系统和喷雾系统结合、R600a等制冷剂为冷却剂的冷却方案,设计了气助式制冷喷雾冷却系统,分析了适用于制冷喷雾冷却系统的工质,提出了喷雾冷却技术在高功率固体激光器散热中的发展方向。     

大功率Nd∶YAG固体激光器

介绍了一台单级输出灯泵浦大功率脉冲Nd∶YAG激光器。该激光器脉宽0.1-10ms可调,频率1-1000hz可调,总注入电功率12kw。试验得到激光器参数脉冲宽度和频率协调改变,可使激光器在整个脉宽范围内都能稳定500w输出;最大单脉冲能量56J;总体电光效率4.2%;光束质量为25mm.mrad;功率稳定性±2%。     

A double-frequency solid-state laser on organic compounds

A double-frequency narrow-band tunable laser with a solid-state organic active medium pumped by the 2nd harmonic of a YAG–Nd³⁺ laser has been developed. The laser emits in the range from uv (with frequency doubling) to near ir wavelengths. The energy and lifetime characteristics of the laser suffice for its practical applications. It can be used as a master oscillator for a high-power narrow-band solid-state laser on organic compounds.     

Optical characterization of tunable solid-state laser gain media

The transition metal ions are optical centres that promise tunable laser operation at room temperature over much of the visible and near-infrared regions. This review presents the essential characteristics used in optical assessment of possible laser-active solids and some of the theory required to understand the experimental results. Also presented is a survey of the main features of the optical absorption-emission cycle, luminescence decay profiles, optical bandshapes and excited-state absorption for Ti³⁺, Cr³⁺ and Co²⁺ ions in (essentially) octahedral environments. Finally, materials characteristics (for example, radiative against non-radiative decay, excited-state absorption and disorder) that limit laser performance are discussed.     

高功率固体多棒激光腔的动态工作特性

 使用等价腔概念，对高功率固体多棒激光腔的动态特性作了分析，推导出了多棒等价g参数和等价腔长的一般公式，由此可得出多棒腔等价g参数图上的动态工作特性曲线和临界光焦度，以数值算例说明多棒腔的动态工作特性。讨论了用适当调整腔镜和棒间距来补偿光焦度偏离的方法，并得出了相应的解析公式。所得结果可作为高功率固体腔设计的参考。     

小分子改性的聚合物固体染料激光特性研究

PMMA是常用的固体染料基质，通过添加乙醇进行改性，形成MPMMA，并对其透过率、荧光光谱、激光光谱和斜率效率进行研究.乙醇对染料的宽带荧光谱的影响较小，荧光谱的带宽为～50nm；激光光谱半宽为7—9 nm，激光光谱的峰值波长随乙醇体积比改变而相应的移动；乙醇体积比存在一个最佳值(15%)，使介质在600 nm—750 nm波段具有最好的透过率(～90%)，并且获得最的斜率效率，其值为49.7%. 关键词： 固体染料 改性聚甲基丙烯酸甲酯 宽带激光 PM567     

Fast wavelength-switching of a diode-pumped solid-state disk laser

The functionality of two experimental setups for fast wavelength-switching of an Yb:YAG disk laser is tested and characterized. The first setup consists of two resonators sharing one disk. Both resonators are alternately opened by a chopper disk. Each resonator is tuned independently by a set of a two-stage Lyot filter and an etalon. Up to 1500 Hz the setup can switch between two freely selectable wavelengths (linewidth (fwhm) ≪1 pm) within the complete Yb:YAG tuning range (from 1020 nm to 1055 nm) emitting a maximum average power of 105 mW. The power of both resonators differs by a factor of 0.7. Their pointing stability amounts to 20 μrad. The second setup consists of a single tunable resonator (two-stage Lyot filter, etalon) additionally equipped with an electro-optical device (Faraday rotator or Pockels cell) providing a high pointing stability of better than 1 μrad. The wavelength switches occur stepwise and are predetermined by the etalon (about 90 pm or multiples thereof). The Faraday rotator suffers from its high thermal load and operates for some few 10 s only at 0.5 Hz. The resonator with the Pockels cell provides long term stability at 1000 Hz, switching steps up to 1.1 nm and a power ratio of 0.83 for the selected wavelengths.