双色双光子阿秒干涉光谱的程函近似模型  

An eikonal approximation model for two-color two-photon attosecond interferometric spectrum

作　　者：屠倩 陈友龙 刘凯[1] 王凤 张晓凡 杨溢 唐富明 廖青 Tu Qian;Chen You-Long;Liu Kai;Wang Feng;Zhang Xiao-Fan;Yang Yi;Tang Fu-Ming;Liao Qing(Hubei Key Laboratory of Optical Information and Pattern Recognition,Wuhan Institute of Technology,Wuhan 430205,China)

机构地区：[1]武汉工程大学,光学信息与模式识别湖北省重点实验室,武汉430205

出　　处：《物理学报》2021年第11期50-56,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11674257,11604248,11874019,11947096,11904269);武汉工程大学校长基金;湖北省高等学校优秀中青年科技创新团队计划(批准号:T201806);湖北省自然科学基金(批准号:2020CFA082)资助的课题。

摘　　要：利用双色双光子阿秒干涉光谱可以在阿秒量级上精确测量光电子从原子、分子以及固体中的电离时间,为人们理解激光辅助单光子电离中的光电子超快发射过程提供了前所未有的推动作用.理解光电子发射时间依赖于物理模型,而目前的模型在预测光电子发射时间上有很大的偏差.于是,本文对之前的程函近似模型进行了改进.与之前的程函近似模型相比,本文模型使用了更准确的末态波函数,并且在计算光电子传播过程中累积的相位时,更准确地计算了光电子轨迹,因而可以更准确地预测光电子发射时间.对比得到的数值模拟结果表明,改进后的程函近似模型比以前的理论模型更加接近含时薛定谔方程的结果,加深了我们对光电子发射超快过程的理解.The emission time of photoelectrons from atoms,molecules and solids can be accurately measured on an attosecond scale by using two-color two-photon attosecond interferometric spectroscopy,which helps us to understand the ultrafast electronic dynamics in laser-assisted single photoionization.Understanding the photoelectron emission time depends on the physical model,and the relevant theoretical model provides a better physical explanation and numerical prediction for the photoemission time delay.Although the numerical solution of the time-dependent Schrödinger equation can accurately predict the photoelectron emission time,but it cannot provide a physical explanation.Although some other current theoretical models can provide a more reasonable corresponding physical process,the quantitative prediction of the photoemission time delay has a large deviation.Therefore,we improve the exisating eikonal approximation model.Comparing with the existing eikonal approximation model,we use a more accurate final state wave function and calculate the photoelectron trajectory more accurately when calculating the phase accumulated in the photoelectron propagation process,so we can predict the photoemission time delay more accurately.By comparing our numerical simulation results,we find that when the final kinetic energy of photoelectron is low,the calculated results from the existing theoretical model are greatly different from those from the time-dependent Schrödinger equation,reaching tens of attoseconds.The resultsfrom the existing theoretical model are closer to those from the time-dependent Schrödinger equation with the increase of final kinetic energy of photoelectron.However,no matter what the final kinetic energy of the photoelectron is,the difference between the calculation result from the improved eikonal approximation model and that from the time-dependent Schrödinger equation is always very small.Therefore,our improved eikonal approximation model is closer to the results from the time-dependent Schrödinger equatio

关 键 词：双色双光子 阿秒干涉 含时薛定谔方程 程函近似模型 

分 类 号：O436.1[机械工程—光学工程]