共查询到20条相似文献,搜索用时 62 毫秒
1.
报道了激光二极管泵浦、采用半导体可饱和吸收镜(SESAM)实现的Nd:GdVO4连续被动锁模运转激光器,得到了较大功率输出(接近1 W)的连续锁模激光.设计了四镜z型折叠激光谐振腔,在不同曲率半径的腔镜及不同的腔长条件下,分别获得了重复频率为250 MHz和100 MHz的稳定连续锁模脉冲输出.采用透过率1%的输出耦合镜,在泵浦功率为6.9 W时,得到连续锁模激光输出功率970 mW,光-光转换率达到13.7%.理论上讨论了调Q锁模的抑制措施,并结合实验结果进行了分析,得到了1063 nm稳定连续锁模激光输出,锁模脉冲光谱宽度1.2 nm(FWHM),用自相关仪测得脉宽为15.1 ps. 相似文献
2.
《中国光学与应用光学文摘》2004,(6)
TN248.1 2004064079 表面态型半导体可饱和吸收镜实现Nd:YAG激光器被动锁模=Passive modelocking diode-end-pumped Nd:YAG laser with surface-state type of semiconductor saturable absorption mirror[刊,中]/王勇刚(中科院半导体所.北京(100083)),马骁宇…∥光电子·激光.—2004,15(5).—446-448 砷化镓半导体材料与空气接触的表面存在密度很高的电子表面态,砷化镓材料内部的电子可以通过这种表面进行弛豫,弛豫时间估计在ps量级。依此原理,制作了一种新型的表面态型半导体可饱和吸收镜,用其作为被 相似文献
3.
利用WS2的可饱和吸收特性,在激光二极管侧面抽运Nd:YAG固体激光器Z型腔结构中分别实现了被动调Q和被动调Q锁模运转。实验表明:当泵浦电流为9.5 A时,开始启动调Q运转,当泵浦电流大于9.8 A时,调Q激光脉冲趋于稳定。当泵浦电流为12.8 A时,被动调Q输出的最大平均功率为466 mW,最窄脉冲宽度为3.205 μs,对应的重复频率为71.70 kHz,此时最大单脉冲能量为6.5 μJ。当泵浦电流达到13.4 A时,激光器实现调Q锁模运转。调Q锁模的最高输出功率为590 mW,调Q包络频率为71.98 kHz,单个调Q包络内的脉冲串重复频率123.1 MHz,每个调Q包络中包含369个脉冲,单脉冲能量为22.2 nJ。结果表明WS2材料可以作为可饱和吸收体用于固体激光器中。 相似文献
4.
5.
在一种掺镱(Yb3+)光纤锁模激光器中。谐振腔采用近“8”字形环形结构,并巧妙地引入半导体可饱和吸收镜(SESAM),腔内引入起偏器和偏振控制器,利用非线性偏振旋转的被动锁模机理,结合SESAM慢可饱和吸收体的自启动作用,在极低的泵浦功率下,实现了稳定的调Q脉冲输出和锁模输出。当泵浦功率为18 mW时,调Q脉冲重复频率为16 kHz,脉冲宽度4 μs,光谱宽度为2.34 nm。当泵浦功率为60 mW时,实现了激光器连续锁模,输出功率8 mW,重复频率20 MHz,光谱宽度3.54 nm,脉宽在ps和亚ps量级,而且在调整偏振控制器的角度时,观察到了波长的调谐现象,调谐范围为1 028~1 530 nm。 相似文献
6.
用脉冲激光二极管阵列(LDA)作为泵浦源、微柱透镜阵列和透镜导管作为耦合系统,以As+注入GaAs可饱和吸收片作为被动调Q锁模元件,实现了Nd∶YVO4激光器调Q锁模运转.调Q运转阶段,激光器每泵浦脉宽内输出一个调Q脉冲,调Q脉宽7ns.调Q锁模运转阶段,初始透过率60%的GaAs晶片对调Q包络内的锁模脉冲的调制深度达到95%以上,锁模脉冲重复频率991 MHz.研究了加在LDA上的电压、方波脉冲的脉宽和重复频率对调Q锁模脉冲特性的影响,并对实验结果进行了讨论. 相似文献
7.
8.
9.
10.
11.
We report the highest average power modelocking of a novel bounce geometry laser using the nonlinear mirror (NLM) technique.
A diode-side pumped Nd:YVO4 slab lasing at 1064 nm in a spatially stigmatic bounce-oscillator configuration was modelocked using a type-I phase-matched
BiBO nonlinear crystal (NLC) in a NLM arrangement, producing 12 W of self-starting, continuous-wave (CW) modelocking. The
system produced a pulse duration of 14 ps at a repetition rate of 110 MHz with high long-term stability and excellent beam
quality, with an M
2<1.2 and highly circular beam profile. An investigation was made of the sensitivity of modelocking as a function of air dispersion,
by varying the distance between the NLC and output coupler. No optical damage was observed throughout the investigation, even
when the system was operated in Q-switched modelocking regime. The system exploits the advantages of NLM modelocking for sustaining
high average and peak powers without the onset of optical damage. 相似文献
12.
The modelocking of a Nd:YAG laser using second-harmonic generation in an external cavity as the only pulse shortening process is reported. The output of a long pulse Nd:YAG laser was simultaneously modelocked and Q-switched. The average pulse duration was 30–50 ps and the peak power was in the range 60–160 kW. 相似文献
13.
Experimental Study of a Pulsed Ytterbium-Doped Fibre Laser with Fast and Slow Saturable Absorbers in a Linear Cavity 下载免费PDF全文
We present a linear-cavity stretched-pulse fibre laser and by semiconductor saturable-absorber mirrors. A with mode locking by a nonlinear polarization rotation Q-switched mode-locking cw train and a mode-locking pulse train are obtained in the experiment. We investigate the effects of the equivalent fast saturable absorber and the slow saturable absorbers in experiment. It is found that neither the nonlinear polarization evolution effect nor a semiconductor saturable absorber mirror is enough to produce the stable cw mode-locking pulses in this experiment. A nonlinear polarization evolution effect controls the cavity loss to literally carve the pulses; semiconductor saturable absorber mirrors provide the self-restarting and maintain the stability of the modelocking operation. 相似文献
14.
We present the performance of diode end-pumped Nd:YVO4 laser in Q-switched and Q-switched mode-locking oscillation using a single-walled carbon nanotube based saturable absorber,
which was fabricated using similar vertical evaporation technique. The average output power, repetition rate and pulse width
of the Q-switched laser output were studied with different output couplers. The maximum average output power was 130 mW. For
Q-switched mode-locking operation, the repetition rate of the mode-locked pulses concentrated in the Q-switched envelope was
58 MHz. The repetition rate of the Q-switched envelope maintained at 18 kHz, while the pulse width decreased along with the
increasing of pump power. The maximum average output power was 53 mW. 相似文献
15.
激光二极管侧面抽运Nd∶YAG锁模激光器的研究 总被引:1,自引:0,他引:1
利用谐振腔的稳定条件对激光二极管侧面抽运的 Nd∶YAG锁模直腔的稳区特性和谐振腔内的光斑分布进行了分析。根据对腔参量的分析,选取合适的腔参量设计了一个简单的侧面抽运直腔,该谐振腔腔形简单,没有像散,振荡光模式好,有利于激光器的锁模运转。实验中采用国内自行研制的半导体可饱和吸收镜,实现了激光二极管侧面抽运半导体可饱和吸收镜锁模Nd∶YAG激光器的连续锁模运转,平均输出功率为 2 W,锁模脉冲宽度为10 ps,重复频率为100 MHz。结合实验结果进一步讨论了半导体可饱和吸收镜的一些参量如饱和恢复时间、调制深度等对实现稳定连续锁模的影响。 相似文献
16.
By the use of installed fibers inside the city we demonstrated a 48.8 km ultralong Erbium-doped fiber laser in modelocking
regime with repetition rate varying from 1–10 GHz. The shortest pulse duration of 42 ps at 2.5 GHz was obtained by optimization
of intracavity dispersion. 相似文献
17.
A wide-band tunable passively Q-switched all-fiber ring laser based on nonlinear polarization rotation (NPR) technique is
demonstrated. The NPR-induced intensity-dependent loss effect acts as an artificial saturable absorber, which was used to
achieve the Q-switched operation with a low pump threshold of about 25 mW. Taking advantage of the intracavity birefringence-induced
spectral filtering effect, the central wavelength of Q-switched pulse can be continuously tuned from 1543.4 to 1592.4 nm by
simply rotating the PCs. 相似文献
18.
被动调Q激光器以其结构简单、紧凑而获得了广泛的应用。为优化其性能参数,在总结近些年被动调Q基本理论基础上,对于具有能量上转换(Energy-transfer upconversion)的激光工作物质构成的被动调Q激光器,提出了可以将能量上转换引起的损耗归到线性损耗中进行优化设计的方法,并给出了输出镜的反射率和饱和吸收体的小信号透过率两者优化选择的直接关系图。根据被动调Q激光器的特有参数α,在总结提高调Q峰值功率的方法基础上,得出当α接近无穷大时,从被动调Q过渡到主动调Q,实现了被动调Q和主动调Q理论的统一。 相似文献
19.
双波长飞秒激光器量子理论研究 总被引:2,自引:0,他引:2
本文建立了一个不涉及具体光腔结构的双波长固体飞秒激光器模型,分析了群达弥散(GVD)、自相位调制(SPM)、交叉耦合、损耗调制和增益放大的动态平衡过程.从场算符的定义出发,导出了双波长飞秒激光器的量子锁模方程组,并且将该量子销模方程组化为经典锁模方程组.结果表明,该方程组和非线性薛定谔方程有着类似的结构,方程组存在稳定的脉冲解,因而从理论上证明了双波长飞秒激光器可以实现双波长同时锁模. 相似文献
20.
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. 相似文献