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Title: Two-photon excitation of low-lying electronic quadrupole states in atomic clusters

Abstract

A simple scheme of population and detection of low-lying electronic quadrupole modes in free small deformed metal clusters is proposed. The scheme is analyzed in terms of the time-dependent local density approximation calculations. As a test case, the deformed cluster Na{sub 11}{sup +} is considered. Long-living quadrupole oscillations are generated via resonant two-photon (two-dipole) excitation and then detected through the appearance of satellites in the photoelectron spectra generated by a probe pulse. Femtosecond pump and probe pulses with intensities I=2x10{sup 10}-2x10{sup 11} W/cm{sup 2} and pulse duration T=200-500 fs are found to be optimal. The modes of interest are dominated by a single electron-hole pair and so their energies, being combined with the photoelectron data for hole states, allow us to gather full mean-field spectra of valence electrons near the Fermi energy. Besides, the scheme allows us to estimate the lifetime of electron-hole pairs and hence the relaxation time of electronic energy into ionic heat.

Authors:
 [1];  [2];  [3];  [4]
  1. Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Moscow region 141980 (Russian Federation)
  2. Institute of Theoretical Physics II, University of Erlangen-Nurnberg, D-91058, Erlangen (Germany)
  3. Department of Physics, Technical University Kaiserslautern, D-67653 (Germany)
  4. Institute of Electronics, Bulgarian Academy of Sciences, Sofia (Bulgaria)
Publication Date:
OSTI Identifier:
20974499
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.73.021201; (c) 2006 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; APPROXIMATIONS; ATOMIC CLUSTERS; DENSITY; DETECTION; DIPOLES; ELECTRONS; EXCITATION; LIFETIME; MEAN-FIELD THEORY; OSCILLATIONS; PHOTOELECTRON SPECTROSCOPY; PHOTONS; POPULATIONS; QUADRUPOLES; RELAXATION TIME; SODIUM IONS; SPECTRA; TIME DEPENDENCE

Citation Formats

Nesterenko, V. O., Reinhard, P.-G., Halfmann, T., and Pavlov, L. I. Two-photon excitation of low-lying electronic quadrupole states in atomic clusters. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.021201.
Nesterenko, V. O., Reinhard, P.-G., Halfmann, T., & Pavlov, L. I. Two-photon excitation of low-lying electronic quadrupole states in atomic clusters. United States. doi:10.1103/PHYSREVA.73.021201.
Nesterenko, V. O., Reinhard, P.-G., Halfmann, T., and Pavlov, L. I. Wed . "Two-photon excitation of low-lying electronic quadrupole states in atomic clusters". United States. doi:10.1103/PHYSREVA.73.021201.
@article{osti_20974499,
title = {Two-photon excitation of low-lying electronic quadrupole states in atomic clusters},
author = {Nesterenko, V. O. and Reinhard, P.-G. and Halfmann, T. and Pavlov, L. I.},
abstractNote = {A simple scheme of population and detection of low-lying electronic quadrupole modes in free small deformed metal clusters is proposed. The scheme is analyzed in terms of the time-dependent local density approximation calculations. As a test case, the deformed cluster Na{sub 11}{sup +} is considered. Long-living quadrupole oscillations are generated via resonant two-photon (two-dipole) excitation and then detected through the appearance of satellites in the photoelectron spectra generated by a probe pulse. Femtosecond pump and probe pulses with intensities I=2x10{sup 10}-2x10{sup 11} W/cm{sup 2} and pulse duration T=200-500 fs are found to be optimal. The modes of interest are dominated by a single electron-hole pair and so their energies, being combined with the photoelectron data for hole states, allow us to gather full mean-field spectra of valence electrons near the Fermi energy. Besides, the scheme allows us to estimate the lifetime of electron-hole pairs and hence the relaxation time of electronic energy into ionic heat.},
doi = {10.1103/PHYSREVA.73.021201},
journal = {Physical Review. A},
number = 2,
volume = 73,
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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