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Title: Theoretical analysis of high-order harmonic generation from a coherent superposition of states

Abstract

A quantum theory of high-order harmonic generation by a strong laser field in the presence of more bound states is formulated. The obtained numerical and analytical results for a two-state hydrogenlike atom model show that the harmonic spectrum consists of two parts: a usual single-state harmonic spectrum of odd harmonics having the energies (2k+1){omega} and a resonant part with the peaks around the excitation energy {delta}{omega}. The energy of the harmonics in the resonant part of the spectrum is equal to {delta}{omega}{+-}{omega}, {delta}{omega}{+-}3{omega}, .... For energies higher than the excitation energy, the resonant part forms a plateau, followed by a cutoff. The emission rate of the harmonics in this resonant plateau is many orders of magnitude higher than that of the harmonics generated in the presence of the ground state alone. The influence of the depletion of the initial states, as well as of the pulse shape and intensity, is analyzed.

Authors:
 [1];  [2]
  1. Faculty of Science, University of Sarajevo, Zmaja od Bosne 35, 71000 Sarajevo (Bosnia and Herzegowina)
  2. (Germany)
Publication Date:
OSTI Identifier:
20768719
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the Optical Society of America. Part B, Optical Physics; Journal Volume: 23; Journal Issue: 2; Other Information: DOI: 10.1364/JOSAB.23.000308; (c) 2006 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMIC MODELS; BEAM OPTICS; BOUND STATE; EXCITATION; GROUND STATES; HARMONIC GENERATION; HARMONICS; HYDROGEN; LASER RADIATION; MULTI-PHOTON PROCESSES; PULSE SHAPERS; SPECTRA

Citation Formats

Milosevic, Dejan B., and Max-Born-Institut, Max-Born-Strasse 2a, Berlin, 12489. Theoretical analysis of high-order harmonic generation from a coherent superposition of states. United States: N. p., 2006. Web. doi:10.1364/JOSAB.23.000308.
Milosevic, Dejan B., & Max-Born-Institut, Max-Born-Strasse 2a, Berlin, 12489. Theoretical analysis of high-order harmonic generation from a coherent superposition of states. United States. doi:10.1364/JOSAB.23.000308.
Milosevic, Dejan B., and Max-Born-Institut, Max-Born-Strasse 2a, Berlin, 12489. Wed . "Theoretical analysis of high-order harmonic generation from a coherent superposition of states". United States. doi:10.1364/JOSAB.23.000308.
@article{osti_20768719,
title = {Theoretical analysis of high-order harmonic generation from a coherent superposition of states},
author = {Milosevic, Dejan B. and Max-Born-Institut, Max-Born-Strasse 2a, Berlin, 12489},
abstractNote = {A quantum theory of high-order harmonic generation by a strong laser field in the presence of more bound states is formulated. The obtained numerical and analytical results for a two-state hydrogenlike atom model show that the harmonic spectrum consists of two parts: a usual single-state harmonic spectrum of odd harmonics having the energies (2k+1){omega} and a resonant part with the peaks around the excitation energy {delta}{omega}. The energy of the harmonics in the resonant part of the spectrum is equal to {delta}{omega}{+-}{omega}, {delta}{omega}{+-}3{omega}, .... For energies higher than the excitation energy, the resonant part forms a plateau, followed by a cutoff. The emission rate of the harmonics in this resonant plateau is many orders of magnitude higher than that of the harmonics generated in the presence of the ground state alone. The influence of the depletion of the initial states, as well as of the pulse shape and intensity, is analyzed.},
doi = {10.1364/JOSAB.23.000308},
journal = {Journal of the Optical Society of America. Part B, Optical Physics},
number = 2,
volume = 23,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}
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