高功率脉冲染料激光放大器物理设计

从理论研究出发,用激光增益理论得到了在平衡状态下忽略染料分子激发态吸收时,高功率脉冲梁料激光放大器物理设计的简单方法,同时以铜蒸气激光器双侧抽运的平均输出功率52.5W的脉冲染料激光放大器为例,对其物理尺寸进行了模拟设计。     

氙灯泵浦新型晶体Nd：S—FAP的激光特性

测量了新型晶体Ｎｄ：Ｓ－ＦＡＰ，（Ｎｄ；Ｓｒ５（ＰＯ４）３Ｆ）的非偏振光吸收光谱，它具有宽的有效吸收带，在５７５ｎｍ和８０４．５ｎｍ处有二个强的吸收峰，采用微型氙灯泵浦实现了自由运转和染料片调Ｑ运转。激光输出波长为１．０５９μｍ，自由运转的阈值能量仅为１５０ｍＪ，斜效率为１．２５％，调Ｑ输出的峰值功率密度为１０ＭＷ／ｃｍ＾２，测量了发射光谱及不同腔长，不同染料片小信号透射率情况下的输出能量，脉冲宽     

准连续60W半导体激光侧面泵浦声光调QNd：YAG板条激光器研究

用准连续６０Ｗ激光二极管列阵侧面泵浦Ｎｄ：ＹＡＧ板条激光器，获得３．５ｍＪ的激光输出和峰值功率为７５ｋＷ的声光调Ｑ激光脉冲，脉冲幅度起伏小于±１％。对研究结果进行了分析。     

氙灯泵浦新型晶体Nd：S—VAP调Q激光器腔内倍频研究

采用氙灯泵浦晶体Ｎｄ：Ｓ－ＶＡＰ，ＫＴＰ晶体腔内倍频，实现了Ｎｄ：Ｓ－ＶＡＰ晶体０．５３２５μｍ绿光激光ＢＤＮ染料片调Ｑ运转，测量了输出绿光激光的特性及不同腔长和染料片小信号透过率情况下的输出能量及脉冲宽度，给出染料片调Ｑ腔内倍频的耦合波方程组，数值求解方程组，所得的理论数据与实验结果很好地相符。     

微微秒叶绿素染料激光器的研究

本文报道用一台对撞脉冲锁模Nd:YAG激光器的三倍频光作为泵浦光源,采用超短腔结构,获得叶绿素的红色ps脉冲激光输出的装置和实验结果。研究了叶绿素a和b在各种聚合状态下输出激光波长随染料浓度的变化关系,当叶绿素a-乙醇溶液浓度为2×10~(-3)M,激光腔长<36μm时可获得单模调谐ps系列脉冲输出,激光束的发散角≈60mrad。     

群速弥散补偿的飞秒激光器的动态性能研究

本文研究了普通的CPM环型染料激光器和棱镜补偿光脉冲的群速度弥散及自相位调制的CPM环型染料激光器的动态性能;实验测量了锁模激光脉冲的光谱随可饱和吸收体DODCI的浓度变化,在腔内正群速度弥散过量时,光脉冲频率发生正啁啾,光谱分布发生反转。     

同步泵浦PML飞秒激光研究

采用CW锁模YAG倍频激光器同步泵浦PML飞秒染料激光器,产生了平均脉宽约55fs、功率为15mW的光脉冲。文章在理论和实验上还研究了同步泵浦飞秒激光脉冲产生技术。     

YAG激光同步泵浦染料激光器产生38fs光脉冲

研究表明,不用碰撞脉冲锁模技术,而由一台简单的线型腔染料激光器,就可成功地产生短达38飞秒的光脉冲。这种激光器用六镜折叠腔,其中有Rh6G和DOPCI两个喷流和一个棱镜对色散补偿器,用连续锁模Nd:YAG激光器的倍频输出同步泵浦。染料激光脉冲的平均功率为20mW,脉冲重复频率近100MHz。     

向列相液晶染料可调谐激光器的研究

对向列相液晶染料的可调谐激光器进行了光学特性研究. 以650 nm为中 心波长设计了SiO₂和TiO₂多层膜的一维光子晶体, 以激光染料与向列相液晶的混合物作为增益介质层, 制备了波长可调谐激光器.用Nd: YAG倍频脉冲激光器输出的532 nm激光抽运所制备的激光器样品得出如下光学特性: 激光发射波长随温度调谐范围为605.5---639.8 nm, 达到34.3 nm, 随电压调谐范围为634.5---619.5 nm, 达到15 nm. 发射激光每脉冲的阈值能量为12.3 μJ, 激光线宽小于1 nm.     

飞秒光脉冲的产生,放大和压缩

评述了飞秒光脉冲研究的现状，其包括同步泵浦连续染料激光器、对碰锁模环形染料激光器、飞秒光脉冲的多级放大和超短光脉冲的压缩．     

Laser system based on a picosecond dye laser with combined feedback for spectroscopy

A laser system comprising a synchronously pumped picosecond dye laser with combined cavity-distributed feedback and a two-stage dye amplifier is described. The dependence of the laser pulse duration on the detuning of the cavity length, the pumping level of the active medium, and the pulse number in the pulse train was investigated. It is shown that the combination of the two types of feedback provides more than ten-fold shortening of the dye laser ultrashort pulse duration. B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 1, pp. 47–55, January–February, 1998.     

Excimer-laser-pumped ps-dye laser

Generation of single dye laser pulses of 12 ps pulse width (FWHM) and 1.2 mJ pulse energy is described using only one XeCl-excimer laser as pump source. At 1 Hz pulse repetition rate the stability of amplitude and pulse width of these pulses is excellent.     

Temporal dynamics of high repetition rate pulsed single longitudinal mode dye laser

Theoretical and experimental studies of temporal dynamics of grazing incidence grating (GIG) cavity, single-mode dye laser pumped by high repetition rate copper vapour laser (CVL) are presented. Spectral chirp of the dye laser as they evolve in the cavity due to transient phase dynamics of the amplifier gain medium is studied. Effect of grating efficiency, focal spot size, pump power and other cavity parameters on the temporal behaviour of narrow band dye laser such as build-up time, pulse shape and pulse width is studied using the four level dye laser rate equation and photon evolution equation. These results are compared with experimental observations of GIG single-mode dye laser cavity. The effect of pulse stretching of CVL pump pulse on the temporal dynamics of the dye laser is studied.     

A parametric study of negative feedback Nd:YAG laser

The output pulse parameters of a mode-locked Nd:YAG laser with a passive negative feedback element were studied experimentally. The pulse evolution within the train was experimentally recorded using a modified second harmonic generation autocorrelator. By comparing the laser operation with and without an acousto-optic modulator, we found that with the later there is a significant increase in the mode locking probability and the pulse acquires a temporally Gaussian symmetric pulse shape. Further with the active modulator there is a relaxation in alignment tolerances and increase in the range of permissible dye concentrations for stable mode locking. It was also observed that the pulse width of the negative feedback laser depends on the saturation intensity of the mode locking dye and reduces for a dye with higher saturation intensity. The pulse width was also found to reduce linearly as the initial transmission of the dye is reduced.     

对撞锁模染料激光器中锁模脉冲列的耦合效应

论述了在对撞锁模染料激光器中必然存在锁模脉冲列耦合效应,此效应使输出脉冲较宽,且脉宽不稳定。用适当加厚锁模染料层等办法减弱该效应会使脉冲变窄且脉宽稳定。     

Generation of nearly transform-limited pulses in subnanosecond region with TEA nitrogen-laser-pumped dye laser

A dye laser is transversely pumped by a TEA nitrogen laser with 700 ps duration. The dye laser pulse has a spectral linewidth of 0.007 nm and a pulse width of ≈ 140 ps, giving a time-bandwidth product of 1.5. It is pointed out that the fluorescence lifetime of the laser dye plays an important role in generation of laser emission using a long laser cavity under subnanosecond pulse pumping.     

Theory of the synchronously pumped picosecond dye laser

The circulation of a synchronously mode locked dye laser pulse in a linear cavity configuration containing a dye cell as an active medium and a bandwidth-limiting element is treated. The condition that the pulse shape reproduces after each cavity round-trip provides a nonlinear integro-differential equation for the steady-state pulse shape. For the solution of this equation an approximate method, not limited to small pulse energies, is given and the pulse duration, intensity, energy, asymmetry of the pulse shape, stable regions and other interesting parameters are discussed.     

Pulse structure studies and absolute cavity length determination for a synchronously pumped picosecond dye laser

Second harmonic cross correlation functions of a pulse with its near neighbor have been studied in a synchronously pumped cw dye laser. Measurements were made both as a function of dye laser cavity length mismatch and the number of cavity round trips separating the correlated pulses. The pulse envelope is found to have a characteristic interpulse frequency determined by the pump laser, whereas the pulse substructure has a characteristic frequency determined by the dye laser cavity length. The cross correlation measurements allow experimental determination of the dye laser length corresponding to exact synchrony. In contrast to theoretical predictions the length of exact synchrony corresponds to optimum pulse shape and duration. Our results are discussed in terms of a simple model which leads to pulse duration estimates as much as twice those obtained by conventional analysis of autocorrelation traces.     

Theory of passively mode-locked cw dye lasers

The circulation of an ultrashort light pulse in a continuously pumped modelocked dye laser with a linear cavity configuration containing the active dye, the saturable absorber and a bandwidth-limiting elements is treated. The steady-state condition that the pulse shape reproduces after each cavity round-trip leads to a nonlinear integro-differential equation for this pulse shape. An approximate method for the solution of this equation not limited to the case of low laser gain and small pulse energies is given. The stable single pulse region and characteristic pulse parameters, as energy, duration, intensity and asymmetry, are considered in dependence on the laser parameters.     

Spectrally Adjustable Picosecond Dye Laser Pulses Generated with Nanosecond Nitrogen Lasers

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