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Title: Pulse-duration dependence of high-order harmonic generation with coherent superposition state

Abstract

We make a systematic study of high-order harmonic generation (HHG) in a He{sup +}-like model ion when the initial state is prepared as a coherent superposition of the ground state and an excited state. It is found that, according to the degree of the ionization of the excited state, the laser intensity can be divided into three regimes in which HHG spectra exhibit different characteristics. The pulse-duration dependence of the HHG spectra in these regimes is studied. We also demonstrate evident advantages of using coherent superposition state to obtain high conversion efficiency. The conversion efficiency can be increased further if ultrashort laser pulses are employed.

Authors:
; ; ; ; ;  [1];  [2]
  1. Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China)
  2. (China)
Publication Date:
OSTI Identifier:
20786337
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 72; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.72.063412; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; CATIONS; CONVERSION; EFFICIENCY; EXCITED STATES; GROUND STATES; HARMONIC GENERATION; HELIUM IONS; LASER RADIATION; PHOTOIONIZATION; PHOTON-ATOM COLLISIONS; PULSES

Citation Formats

Wang Bingbing, Cheng Taiwang, Li Xiaofeng, Fu Panming, Chen Shigang, Liu Jie, and Institute of Applied Physics and Computational Mathematics, Beijing 100088. Pulse-duration dependence of high-order harmonic generation with coherent superposition state. United States: N. p., 2005. Web. doi:10.1103/PHYSREVA.72.0.
Wang Bingbing, Cheng Taiwang, Li Xiaofeng, Fu Panming, Chen Shigang, Liu Jie, & Institute of Applied Physics and Computational Mathematics, Beijing 100088. Pulse-duration dependence of high-order harmonic generation with coherent superposition state. United States. doi:10.1103/PHYSREVA.72.0.
Wang Bingbing, Cheng Taiwang, Li Xiaofeng, Fu Panming, Chen Shigang, Liu Jie, and Institute of Applied Physics and Computational Mathematics, Beijing 100088. Thu . "Pulse-duration dependence of high-order harmonic generation with coherent superposition state". United States. doi:10.1103/PHYSREVA.72.0.
@article{osti_20786337,
title = {Pulse-duration dependence of high-order harmonic generation with coherent superposition state},
author = {Wang Bingbing and Cheng Taiwang and Li Xiaofeng and Fu Panming and Chen Shigang and Liu Jie and Institute of Applied Physics and Computational Mathematics, Beijing 100088},
abstractNote = {We make a systematic study of high-order harmonic generation (HHG) in a He{sup +}-like model ion when the initial state is prepared as a coherent superposition of the ground state and an excited state. It is found that, according to the degree of the ionization of the excited state, the laser intensity can be divided into three regimes in which HHG spectra exhibit different characteristics. The pulse-duration dependence of the HHG spectra in these regimes is studied. We also demonstrate evident advantages of using coherent superposition state to obtain high conversion efficiency. The conversion efficiency can be increased further if ultrashort laser pulses are employed.},
doi = {10.1103/PHYSREVA.72.0},
journal = {Physical Review. A},
number = 6,
volume = 72,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
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