Effect of electron correlation on high-order-harmonic generation of helium atoms in intense laser fields: Time-dependent generalized pseudospectral approach in hyperspherical coordinates
Authors:
- Xiaoxu GuanXGXiaoxu Guan
- Xiao-Min TongXTXiao-Min Tong
Open Access
- 2 February 2006
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review A
- Vol. 73 (2)
Abstract
We present a time-dependent generalized pseudospectral TDGPS approach in hyperspherical coordinates for fully ab initio nonperturbative treatment of multiphoton dynamics of atomic systems in intense laser fields. The procedure is applied to the investigation of high-order-harmonic generation HHG of helium atoms in ultrashort laser pulses at a KrF wavelength of 248.6 nm. The six-dimensional coupled hyperspherical- adiabatic-channel equations are discretized and solved efficiently and accurately by means of the TDGPS method. The effects of electron correlation and doubly excited states on HHG are explored in detail. A HHG peak with Fano line profile is identified which can be attributed to a broad resonance of doubly excited states. Comparison of the HHG spectra of the ab initio two-electron and the single-active-electron model calculations is also presented.Keywords
This publication has 34 references indexed in Scilit:
- Double photoexcitation of He atoms by attosecond xuv pulses in the presence of intense few-cycle infrared lasersPhysical Review A, 2005
- Role of the electronic structure and multielectron responses in ionization mechanisms of diatomic molecules in intense short-pulse lasers: An all-electronab initiostudyPhysical Review A, 2004
- Colloquium: Femtosecond optical frequency combsReviews of Modern Physics, 2003
- Multiphoton ionization and high-order harmonic generation of He, Ne, and Ar atoms in intense pulsed laser fields: Self-interaction-free time-dependent density-functional theoretical approachPhysical Review A, 2001
- Self-interaction-free time-dependent density-functional theory for molecular processes in strong fields: High-order harmonic generation ofin intense laser fieldsPhysical Review A, 2001
- Time-dependent approach to high-resolution spectroscopy and quantum dynamics of Rydberg atoms in crossed magnetic and electric fieldsPhysical Review A, 2000
- Doubly excited,, andresonances in He below thethresholdPhysical Review A, 1997
- Generation of Coherent X-rays in the Water Window Using 5-Femtosecond Laser PulsesScience, 1997
- Generation of Coherent Soft X Rays at 2.7 nm Using High HarmonicsPhysical Review Letters, 1997
- Wavelength dependence of nonsequential double ionization in HePhysical Review A, 1993