江西师范大学学报(自然科学版)
江西師範大學學報(自然科學版)
강서사범대학학보(자연과학판)
JOURNAL OF JIANGXI NORMAL UNIVERSITY(NATURAL SCIENCES EDITION)
2014年
5期
464-467
,共4页
激光传播%部分离化等离子体%焦斑半径%脉冲宽度%自相位调制
激光傳播%部分離化等離子體%焦斑半徑%脈遲寬度%自相位調製
격광전파%부분리화등리자체%초반반경%맥충관도%자상위조제
laser propagation%partially stripped plasmas%laser spot size%laser pulse length%group velocity dispersion
采用变分法推导出有限长激光脉冲在部分离化等离子体中的参数演化方程,其中包含群速度色散和自相位调制的影响,通过分析焦斑半径和脉冲宽度满足的耦合方程,详细讨论了等离子体密度对激光脉冲传播特性影响。研究结果表明:在部分离化等离子体中,对于给定强度的激光脉冲,随着等离子体密度增大,自相位调制会进一步增强激光脉冲的自聚焦;当等离子体密度增大时,激光脉冲传播频率由负向啁啾变化转变为正向啁啾频率变化,而且随着传播距离增大,激光脉冲红移减小而蓝移增大。研究结果对有限长激光脉冲电离诱导自注入加速电子的方案具有理论指导意义。
採用變分法推導齣有限長激光脈遲在部分離化等離子體中的參數縯化方程,其中包含群速度色散和自相位調製的影響,通過分析焦斑半徑和脈遲寬度滿足的耦閤方程,詳細討論瞭等離子體密度對激光脈遲傳播特性影響。研究結果錶明:在部分離化等離子體中,對于給定彊度的激光脈遲,隨著等離子體密度增大,自相位調製會進一步增彊激光脈遲的自聚焦;噹等離子體密度增大時,激光脈遲傳播頻率由負嚮啁啾變化轉變為正嚮啁啾頻率變化,而且隨著傳播距離增大,激光脈遲紅移減小而藍移增大。研究結果對有限長激光脈遲電離誘導自註入加速電子的方案具有理論指導意義。
채용변분법추도출유한장격광맥충재부분리화등리자체중적삼수연화방정,기중포함군속도색산화자상위조제적영향,통과분석초반반경화맥충관도만족적우합방정,상세토론료등리자체밀도대격광맥충전파특성영향。연구결과표명:재부분리화등리자체중,대우급정강도적격광맥충,수착등리자체밀도증대,자상위조제회진일보증강격광맥충적자취초;당등리자체밀도증대시,격광맥충전파빈솔유부향조추변화전변위정향조추빈솔변화,이차수착전파거리증대,격광맥충홍이감소이람이증대。연구결과대유한장격광맥충전리유도자주입가속전자적방안구유이론지도의의。
In the presence of self-phase modulation,and group velocity dispersion,the propagation characteristics of a short laser pulse in partially stripped plasma are investigated. A variational technique is used to obtain equations describing the evolution of the laser spot size and pulse length,analyzing the effects of the plasma density on the propagation of a short laser pulse in partially stripped plasma. It is found that the laser pulse can be allowed to prop-agate in patitally stripped plasma only when a certain relation for laser parameters and plasma parameters is satis-fied. The plasma density has affected the laser focusing enhanced efficiently. As compared to fully ionized plasma,in partially stripped plasma,plasma density play a critical role of the laser focusing. The results may be significant the-oretically to the mechanism of ionization-induced injection and acceleration by an intense laser pulse.