Ways to produce and measure atto- and femtosecond soft X-ray pulses  

作　　者：GE YuCheng 

机构地区：[1]Department of Technical Physics and DOE Key Laboratory of Heavy Ion Physics, Peking University, Beijing 100871, China

出　　处：《Chinese Science Bulletin》2007年第9期1172-1177,共6页

基　　金：Supported by the National Natural Science Foundation of China (Grant No. 10675014)

摘　　要：The ways to produce and measure atto-and femtosecond soft X-ray pulses are reported. The laser phase relation of high-order harmonic generation(HHG) shows two different radiation energy distribu-tions in time(or laser phase) domain. These energy-phase relations are helpful for realizing the dy-namic processes of HHG. Two presented parameterized formulas can be used to calculate the durations of the energy distributions with a bandwidth of the pulse. These formulas are useful in calculating and simulating pulses transports and interactions with mediums. The time structures of atto-and femto-second soft X-ray pulses can be directly measured with photoelectron spectrum transfer equations and the related laser phase determination methods without any previous pulse shape and the instantane-ous frequency assumptions. These equations and methods can be used to evaluate and improve the technical parameters of the ultra-short X-ray sources. They have wide measurement ranges and high time resolutions,which may enable ultra-fast measurements to reach metrological precisions,and lead to a new tide of scientific researches in physics,chemistry,biochemistry,etc. The application of atto-and femtosecond X-rays as well as the theoretical and technical problems in measurements are briefly discussed.The ways to produce and measure atto- and femtosecond soft X-ray pulses are reported. The laser phase relation of high-order harmonic generation （HHG） shows two different radiation energy distributions in time （or laser phase） domain. These energy-phase relations are helpful for realizing the dynamic processes of HHGL Two presented parameterized formulas can be used to calculate the durations of the energy distributions with a bandwidth of the pulse. These formulas are useful in calculating and simulating pulses transports and interactions with mediums. The time structures of atto- and femtosecond soft X-ray pulses can be directly measured with photoelectron spectrum transfer equations and the related laser phase determination methods without any previous pulse shape and the instantaneous frequency assumptions. These equations and methods can be used to evaluate and improve the technical parameters of the ultra-short X-ray sources. They have wide measurement ranges and high time resolutions, which may enable ultra-fast measurements to reach metrological precisions, and lead to a new tide of scientific researches in physics, chemistry, biochemistry, etc. The application of attoand femtosecond X-rays as well as the theoretical and technical problems in measurements are briefly discussed.

关 键 词：原秒软X射线脉冲 飞秒软X射线脉冲 产生途径 测量方法 高阶谐波 

分 类 号：O571.32[理学—粒子物理与原子核物理]