共查询到19条相似文献,搜索用时 578 毫秒
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《中国光学与应用光学文摘》2007,(4)
O4372007043291光学参变啁啾脉冲放大相位失配啁啾脉冲频谱整形新方法=New method of chirped-pulse spectral shaping usingphase mismatched optical parametric chirped pulse amplifi-cation[刊,中]/邓青华(中物院激光聚变研究中心.四川,绵阳(621900)),彭翰生…//光学学报. 相似文献
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高功率钕玻璃啁啾脉冲放大系统光谱整形 总被引:2,自引:1,他引:1
增益窄化效应限制了啁啾脉冲放大系统输出的最短脉冲宽度,需要对注入放大系统的种子啁啾脉冲进行光谱整形,以保证放大后的啁啾脉冲光具有足够的带宽并满足特定的光谱分布.理论上假定放大后啁啾脉冲的光谱分布为高斯分布或超高斯分布,对"百焦耳级钕玻璃啁啾脉冲放大系统"进行逆运算.研究发现,所需种子啁啾光的能量、带宽以及压缩后脉冲的信噪比都与该分布密切相关.通过光谱整形,使放大后的啁啾脉冲光的光谱分布为二阶超高斯分布.能够获得小于400 fs高信噪比的超短脉冲输出,此时所需种子啁啾脉冲能量仅为33μJ,带宽14 nm,在装置前级注入能力的范围之内.为百焦耳装置光谱整形实验的开展提供了理论指导. 相似文献
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针对具有非线性负啁啾的超高斯脉冲,提出了一种双余弦相位调制方法,采用该方法对高非线性光纤中超高斯脉冲的频谱压缩进行优化。结果表明:由于初始超高斯脉冲的非线性负啁啾与非线性光纤中自相位调制引起的正啁啾失配导致时间相位不平坦,频谱出现分裂和旁瓣,压缩质量受限。通过对超高斯脉冲进行外部的两个余弦相位补偿调制可以减少频谱旁瓣的产生,延长频谱压缩距离,提高频谱压缩质量;其中这两个余弦相位调制的振幅和频率来自于对超高斯脉冲的非线性相移分析;在大范围展宽因子下,超高斯脉冲的频谱压缩质量也可以优化。 相似文献
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首先介绍了模拟光参量啁啾脉冲放大(OPCPA)过程的多种计算模型,在此基础上提出了三步走逐步逼近算法,以确定OPCPA过程中最稳输出时所需的非线性晶体长度.这种算法综合利用了上述计算模型,随着计算模型越来越精确,非线性晶体长度的计算范围越来越小.因而利用这种算法能高效、精确地确定最佳非线性晶体长度.最后提出在OPCPA过程引入一定的相位失配量,来调谐最稳输出时所需晶体长度,从而能突破晶体加工精度不够的局限,在实际OPCPA过程中获得稳定输出. 相似文献
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首先介绍了模拟光参量啁啾脉冲放大(OPCPA)过程的多种计算模型,在此基础上提出了三步走逐步逼近算法,以确定OPCPA过程中最稳输出时所需的非线性晶体长度.这种算法综合利用了上述计算模型,随着计算模型越来越精确,非线性晶体长度的计算范围越来越小.因而利用这种算法能高效、精确地确定最佳非线性晶体长度.最后提出在OPCPA过程引入一定的相位失配量,来调谐最稳输出时所需晶体长度,从而能突破晶体加工精度不够的局限,在实际OPCPA过程中获得稳定输出.
关键词:
光参量啁啾脉冲放大
最稳输出
相位失配
非线性晶体长度 相似文献
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研究和建议了一种用于产生亚12fs脉冲的基于脉冲波前匹配的LBO超宽带光学参量啁啾脉冲放大器。实验结果表明LBO超宽带光学参量啁啾脉冲放大器可以输出大于60nm(FWHM)的增益光谱带宽,为了利用这种放大器产生转换限制的脉冲输出,给出了一种将超宽带光学参量啁啾脉冲放大器与脉冲波前匹配相结合的方法,这种方法等价于信号光脉冲波前无斜置的放大,克服了超宽带参量啁啾脉冲放大器中由于信号光的脉冲波前斜置而导致很难获得最短压缩脉冲输出的缺陷,从而允许产生转换限制的亚12fs脉冲。 相似文献
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Phase matched scanning optical parametric chirped pulse amplification based on pump beam deflection 下载免费PDF全文
《中国物理 B》2021,30(10):104209-104209
Combined with the optical beam deflection, a novel approach of phase matched broadband scanning optical parametric chirped pulse amplification(OPCPA) was proposed. For this scheme, there was no superfluous operations to the chirped signal pulse which propagated in a changeless direction straightforward, but the pump beam were deflected in space with time by passing through a KTN crystal, which was applied with varied driving voltage. The theories of phase matching of each chirped signal frequency based on pump beam deflection was analyzed detailedly. And the type-I amplification of chirped signal with 800 nm central wavelength and 20 nm bandwidth pumped by 532 nm in BBO crystal was simulated as a case in point. The simulation results showed that the spectral distribution of chirped signal pulse was almost the same as the initial form, i.e., there was nearly no narrowing on the amplified spectrum by using of the scanning OPCPA based on pump beam deflection. In addition, the simulations demonstrated that it was worth minimizing the voltage deviation applied to KTN crystal as much as possible for the sake of better waveform, larger bandwidth and higher conversion efficiency of amplified signal pulse in the proposed scanning OPCPA. 相似文献
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Trends in ultrashort and ultrahigh power laser pulses based on optical parametric chirped pulse amplification 下载免费PDF全文
Since the proof-of-principle demonstration of optical parametric amplification to efficiently amplify chirped laser pulses in 1992,optical parametric chirped pulse amplification(OPCPA)became the most promising method for the amplification of broadband optical pulses.In the meantime,we are witnessing an exciting progress in the development of powerful and ultrashort pulse laser systems that employ chirped pulse parametric amplifiers.The output power and pulse duration of these systems have ranged from a few gigawatts to hundreds of terawatts with a potential of tens of petawatts power level.Meanwhile,the output pulse duration based on optical parametric amplification has entered the range of fewoptical-cycle field.In this paper,we overview the basic principles,trends in development,and current state of the ultrashort and laser systems based on OPCPA,respectively. 相似文献
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光参量啁啾脉冲放大(OPCPA)是超短激光脉冲领域的重要技术之一,增大增益带宽对提高OPCPA的转换效率、实现宽带光参量放大具有重要的意义.本文将光束偏转和非共线OPCPA有机结合,提出了基于光束偏转的扫描式宽带OPCPA模型.分析了通过光束偏转来时刻改变非共线角,以保证各频率成分的相位匹配,从而增大增益带宽的基本原理.采用提出的扫描式宽带OPCPA,针对800 nm中心波长、带宽约为100 nm信号光的光参量放大进行了数值计算.结果表明:经过扫描式OPCPA后,信号光的带宽与放大之前几乎相同,光谱没有窄化;扫描式OPCPA比固定非共线角方式的放大极大地增加了增益带宽和转换效率,实现了宽带的光参量放大;要满足信号光各频率成分的相位匹配,达到最大的增益带宽和转换效率,需要尽量减小加载到钽铌酸钾(KTa_(1-x) Nb_xO_3, KTN)电光晶体上的电压抖动和电压延时. 相似文献
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利用大啁啾信号光脉冲的光谱在时域内的分布特点,采用四阶龙格-库塔算法对宽光谱的光参量啁啾脉冲放大(OPCPA)激光器特性进行了数值分析。以LBO晶体为增益介质,信号光脉冲宽度取100 ps、啁啾系数为1 000,中心波长为800 nm;泵浦光的中心波长为532 nm,脉宽为100 ps。数值计算结果表明:信号光的非线性相位变化的中心部分为线性分布区,且随增益饱和的程度增大而增大;系统的功率转换效率有准振荡结构,且其第一个极值点为系统能量最大的转换率点;随着系统进入增益饱和区,压缩光脉冲的对比度明显降低,预脉冲长度显著增大。 相似文献