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Title: Laser Phase Control of High-Order Harmonic Generation at Large Internuclear Distance: The H{sup +}-H{sub 2}{sup +} System

Abstract

Exact (Born-Oppenheimer) 3-D numerical solutions of the time-dependent Schroedinger equation are obtained for the one electron linear H{sup +}-H{sub 2}{sup +} atom-molecule system at large internuclear distance R in interaction with two-cycles intense (I>10{sup 14} W cm{sup -2}) 800 nm laser pulses. High-order harmonic generation (HHG) spectra are obtained with an energy cutoff larger than the atomic maximum of I{sub p}+3U{sub p}, where I{sub p} is the ionization potential and U{sub p} is the ponderomotive energy. At large R, this extended cutoff is shown to be related to the nature of electron transfer, whose direction is shown to depend critically on the carrier-envelope phase (CEP) of the ultrashort pulse. Constructive and destructive interferences in the HHG spectrum resulting from coherent superpositions of electronic states in the H{sup +}-H{sub 2}{sup +} system are interpreted in terms of multiple electron trajectories extracted from a time profile analysis.

Authors:
; ;  [1]
  1. Laboratoire de Chimie Theorique, Faculte des Sciences, Universite de Sherbrooke, Sherbrooke, Quebec, J1K 2R2 (Canada)
Publication Date:
OSTI Identifier:
20861578
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevLett.98.013001; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BORN-OPPENHEIMER APPROXIMATION; ELECTRON TRANSFER; ELECTRONS; HARMONIC GENERATION; HYDROGEN IONS 1 PLUS; HYDROGEN IONS 2 PLUS; INTERFERENCE; IONIZATION POTENTIAL; NUMERICAL SOLUTION; PONDEROMOTIVE FORCE; SCHROEDINGER EQUATION; THREE-DIMENSIONAL CALCULATIONS; TIME DEPENDENCE; TRAJECTORIES

Citation Formats

Bandrauk, Andre D., Barmaki, Samira, and Kamta, Gerard Lagmago. Laser Phase Control of High-Order Harmonic Generation at Large Internuclear Distance: The H{sup +}-H{sub 2}{sup +} System. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.013001.
Bandrauk, Andre D., Barmaki, Samira, & Kamta, Gerard Lagmago. Laser Phase Control of High-Order Harmonic Generation at Large Internuclear Distance: The H{sup +}-H{sub 2}{sup +} System. United States. doi:10.1103/PHYSREVLETT.98.013001.
Bandrauk, Andre D., Barmaki, Samira, and Kamta, Gerard Lagmago. Fri . "Laser Phase Control of High-Order Harmonic Generation at Large Internuclear Distance: The H{sup +}-H{sub 2}{sup +} System". United States. doi:10.1103/PHYSREVLETT.98.013001.
@article{osti_20861578,
title = {Laser Phase Control of High-Order Harmonic Generation at Large Internuclear Distance: The H{sup +}-H{sub 2}{sup +} System},
author = {Bandrauk, Andre D. and Barmaki, Samira and Kamta, Gerard Lagmago},
abstractNote = {Exact (Born-Oppenheimer) 3-D numerical solutions of the time-dependent Schroedinger equation are obtained for the one electron linear H{sup +}-H{sub 2}{sup +} atom-molecule system at large internuclear distance R in interaction with two-cycles intense (I>10{sup 14} W cm{sup -2}) 800 nm laser pulses. High-order harmonic generation (HHG) spectra are obtained with an energy cutoff larger than the atomic maximum of I{sub p}+3U{sub p}, where I{sub p} is the ionization potential and U{sub p} is the ponderomotive energy. At large R, this extended cutoff is shown to be related to the nature of electron transfer, whose direction is shown to depend critically on the carrier-envelope phase (CEP) of the ultrashort pulse. Constructive and destructive interferences in the HHG spectrum resulting from coherent superpositions of electronic states in the H{sup +}-H{sub 2}{sup +} system are interpreted in terms of multiple electron trajectories extracted from a time profile analysis.},
doi = {10.1103/PHYSREVLETT.98.013001},
journal = {Physical Review Letters},
number = 1,
volume = 98,
place = {United States},
year = {Fri Jan 05 00:00:00 EST 2007},
month = {Fri Jan 05 00:00:00 EST 2007}
}
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