阿秒脈衝激發和遠紅外雷射驅動中稀有氣體原子的光子發射譜中的半脈衝週期震盪: 自作用修正的隨時變密度泛函理論計算

Subcycle Dynamics of Photon Emission Spectra of Rare Gases Atoms Excited by Attosecond Pulses and Driven by Near-Infrared Laser Field: Self-Interaction-Free Time-Dependent Density-Functional-Theory Approach

周繼暉(Chi-Hui Chou)

指導教授 ： 朱時宜

國立臺灣大學/理學院/應用物理所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.00820

摘要

本文應用了自作用修正的隨時變密度泛涵理論和非微擾的數值計算方法，計算阿秒脈衝激發和遠紅外雷射驅動中氫、氦和氖原子的光子發射譜，藉由改變阿秒脈衝和遠紅外雷射的時間差，我們可以觀察到半雷射周期的震盪以及能階的改變。這種現象已從吸收光譜實驗上觀察到，我們也計算出激發態的電子機率隨時間差有著相同的週期震盪，我們從兩個光子吸收觀點來解釋這種現象。

關鍵字

阿秒脈衝 ； 自作用修正時變密度泛涵理論 ； 半雷射週期現象

並列摘要

We present an ab initio method to study the sub-cycle dynamics of hydrogen, helium and neon atoms in near-infrared(NIR) laser fields subject to excitation by a single extreme ultraviolet attosecond pulse(SAP). We extended the self-interaction-free time-dependent density functional theory(TD-KLI-SIC) to describe multi-electron system and solve the time-dependent Kohn-Sham equations by time-dependent generalized pseudospectral(TDGPS) method. We calculated the photon emission spectra and population of several excited states as the function of the time delay between the NIR pulse and SAP. The phenomena can be explain by two-photon absorption.

並列關鍵字

attosecond ； time dependent density functional theory ； subcycle dynamics

參考文獻

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