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Title: Electronic Raman scattering and the renormalization of the electron spectrum in LuB{sub 12}

Abstract

The electronic Raman scattering in LuB{sub 12} single crystals of various isotope compositions is studied in the temperature range 10–650 K. The shape and the energy position of spectral maxima depend on the direction and magnitude of a probe wavevector, the temperature, and the excitation symmetry and remain unchanged when the isotope composition changes. Experimental spectra are compared with the spectra simulated on the basis of a calculated electronic structure. The experimental results are successfully described when the electron spectrum renormalization effects caused by electron–phonon coupling are taken into account. This confirms that the origin of the observed spectra in LuB{sub 12} is due to Raman scattering by electrons. A comparison of the calculated and experimental data makes it possible to determine the coupling constant (λ{sub ep} = 0.32) that gives the correct superconducting transition temperature.

Authors:
;  [1]; ;  [2]
  1. Russian Academy of Sciences, Institute of Metal Physics, Ural Branch (Russian Federation)
  2. National Academy of Sciences of Ukraine, Frantsevich Institute of Materials Science Problems (Ukraine)
Publication Date:
OSTI Identifier:
22617180
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 123; Journal Issue: 3; Other Information: Copyright (c) 2016 Pleiades Publishing, Inc.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; COMPARATIVE EVALUATIONS; COUPLING CONSTANTS; ELECTRON SPECTRA; ELECTRON-PHONON COUPLING; ELECTRONS; EXCITATION; ISOTOPE RATIO; ISOTOPES; LUTETIUM BORIDES; MONOCRYSTALS; RAMAN EFFECT; RENORMALIZATION; SIMULATION; SYMMETRY; TRANSITION TEMPERATURE

Citation Formats

Ponosov, Yu. S., E-mail: ponosov@imp.uran.ru, Streltsov, S. V., E-mail: streltsov@gmail.com, Levchenko, A. V., and Filippov, V. B.. Electronic Raman scattering and the renormalization of the electron spectrum in LuB{sub 12}. United States: N. p., 2016. Web. doi:10.1134/S1063776116090077.
Ponosov, Yu. S., E-mail: ponosov@imp.uran.ru, Streltsov, S. V., E-mail: streltsov@gmail.com, Levchenko, A. V., & Filippov, V. B.. Electronic Raman scattering and the renormalization of the electron spectrum in LuB{sub 12}. United States. doi:10.1134/S1063776116090077.
Ponosov, Yu. S., E-mail: ponosov@imp.uran.ru, Streltsov, S. V., E-mail: streltsov@gmail.com, Levchenko, A. V., and Filippov, V. B.. 2016. "Electronic Raman scattering and the renormalization of the electron spectrum in LuB{sub 12}". United States. doi:10.1134/S1063776116090077.
@article{osti_22617180,
title = {Electronic Raman scattering and the renormalization of the electron spectrum in LuB{sub 12}},
author = {Ponosov, Yu. S., E-mail: ponosov@imp.uran.ru and Streltsov, S. V., E-mail: streltsov@gmail.com and Levchenko, A. V. and Filippov, V. B.},
abstractNote = {The electronic Raman scattering in LuB{sub 12} single crystals of various isotope compositions is studied in the temperature range 10–650 K. The shape and the energy position of spectral maxima depend on the direction and magnitude of a probe wavevector, the temperature, and the excitation symmetry and remain unchanged when the isotope composition changes. Experimental spectra are compared with the spectra simulated on the basis of a calculated electronic structure. The experimental results are successfully described when the electron spectrum renormalization effects caused by electron–phonon coupling are taken into account. This confirms that the origin of the observed spectra in LuB{sub 12} is due to Raman scattering by electrons. A comparison of the calculated and experimental data makes it possible to determine the coupling constant (λ{sub ep} = 0.32) that gives the correct superconducting transition temperature.},
doi = {10.1134/S1063776116090077},
journal = {Journal of Experimental and Theoretical Physics},
number = 3,
volume = 123,
place = {United States},
year = 2016,
month = 9
}
  • No abstract prepared.
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