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101.
K P J Reddy 《Pramana》1985,25(6):713-718
The analysis of the characteristics of a synchronously mode-locked and internally frequency-doubled dye laser is presented.
Dependence of dye laser pulse characteristics on the cavity length mismatch of the pump laser and dye laser is studied. Variation
of the minimum pulsewidth with intracavity bandwidth and the harmonic conversion efficiency is presented in the form of graphs. 相似文献
102.
Fei Chen Xin Yu Xudong Li Renpeng Yan Cheng Wang Deying Chen Zhonghua Zhang Junhua Yu 《Optics Communications》2011,284(2):635-639
A high power diode-end-pumped passively Q-switched and mode-locking (QML) Nd:GdVO4 laser at 912 nm was demonstrated for the first time, to the best of our knowledge. A Z-type laser cavity with Cr4+:YAG crystals as the intracavity saturable absorber were employed in the experiments. Influence of the initial transmission (TU) of the saturable absorber on the QML laser performance was investigated. Using the TU = 95% Cr4+:YAG, as much as an average output power of 2.0 W pulsed 912 nm laser was produced at an absorbed pump power of 25.0 W, then the repetition rates of the Q-switched envelope and the mode-locking pulse were ~ 224 kHz and ~ 160 MHz, respectively. Whereas the maximum output power was reduced to 1.3 W using the TU = 90% Cr4+:YAG, we obtained a 100% modulation depth for the mode-locking pulses inside the Q-switched envelope. 相似文献
103.
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105.
Sequential generation of self-starting diverse operations in all-fiber laser based on thulium-doped fiber saturable absorber 下载免费PDF全文
Self-starting Q-switching, Q-switched mode-locking and mode-locking operation modes are achieved sequentially in an all-fiber erbium-doped fiber laser with thulium-doped fiber saturable absorber for the first time. The central wavelengths of Q-switching, Q-switched mode-locking and mode-locking operation modes are 1569.7 nm, 1570.9 nm, and 1572 nm, respectively. The mode-locking operation of the proposed fiber laser generates stable dark soliton with a repetition rate of 0.99 MHz and signal-to-noise ratio of 65 dB. The results validate the capability of generating soliton pulse by doped fiber saturable absorber. Furthermore, the proposed fiber laser is beneficial to the applications of optical communication and signal processing system. 相似文献
106.
All-fiber erbium-doped dissipative soliton laser with multimode interference based on saturable-reserve saturable hybrid optical switch 下载免费PDF全文
Reverse saturable absorption is essential for the realization of dissipative solitons. In this paper, we introduce reverse saturable absorption by using nonlinear multimode interference (NL-MMI), for the first time, to the best of our knowledge, and obtain a stable dissipative soliton operation. By adjusting the coupling efficiency from multimode fiber to single mode fiber, the absorption properties of NL-MMI can be switched between saturation and reverse saturation. The dissipative soliton can be obtained with pulse width of 975 fs in the experiment, the 3-dB bandwidth at 1555 nm is 16 nm, and the maximum output power is 11.48 mW. The nonlinear absorption optical modulation and high damage threshold characteristics of the NL-MMI based ultrafast optical switch provide a new idea for realizing dissipative solitons. 相似文献
107.
介绍一种采用主动锁模控制产生超短激光脉冲序列的方法。首先通过基于主动锁模激光系统的参量自治微分方程思想,导出了系统出现稳定条件时参数设置方法。然后利用铌酸锂的非线性,展开成贝赛尔系数的函数级数,载频与边频数差为调制频率的整数倍,最后产生高重复频率超短光脉冲,得到高阶锁模脉冲,实验结果表明:其通过调节调制器的调制参数来控制谐振腔中的模式损耗,在调制频率为1GHz量级的情况下,可获得重复频率10GHz的超短光脉冲序列,有啁啾时脉冲时域形状是很好的高斯型,没有出现明显畸变。 相似文献
108.
基于Cr:YAG的调Q锁模Nd:GdVO4自受激拉曼激光器 总被引:5,自引:5,他引:0
以Cr:YAG作为饱和吸收体,利用a向切割的Nd:GdVO4晶体的自受激拉曼散射效应,实现了 结构紧凑的1173nm拉曼激光器的调Q锁模输出。Nd:GdVO4晶体长度为10mm,Nd 3+离子掺杂浓度为0.2%;Gr:YAG晶体的初始透过率为70%。激光器为LD端面泵浦,折叠腔结构,并且采 用了透过率为10%的输出镜。泵浦功率5W时激 光开始振荡输出。锁模脉冲重复频率高达900MHz;在最高泵浦功率时,1173nm 激光平均输出功率为180mW,调Q包络宽 度为11ns。同时,利用10mm长的Ⅰ类匹配 LBO作倍频晶体,成功实现了锁模黄光的输出,输出平均功率为10mW 。并对586.5nm脉冲黄光的光谱进行了测量。激光器设计合理,热效 应对激光器的影响被有效抑制。 相似文献
109.
A self-starting mode-locked femtosecond laser is accomplished with an oxoborate self-frequency doubling crystal Yb:YCa4O(BO3)3(Yb:YCOB) as the gain medium and a semiconductor mirror as the saturable absorber. Pumped by a976-nm fiber-coupled diode laser with 50-μm core diameter, stable mode-locked laser pulses up to 430 mW were obtained at a repetition rate of 83.61 MHz under 5-W pump power. The autocorrelation measurement shows that the pulse duration is as short as 150 fs by assuming the sech2pulse shape at a central wavelength of 1048 nm. This work has demonstrated a compact and reliable femtosecond laser source for prospective low-cost applications. 相似文献
110.