, Volume 71, Issue 4, pp 687–693 | Cite as

Phonon linewidths in YNi2B2C

  • L. PintschoviusEmail author
  • F. Weber
  • W. Reichardt
  • A. Kreyssig
  • R. Heid
  • D. Reznik
  • O. Stockert
  • K. Hradil


Phonons in a metal interact with conduction electrons which give rise to a finite linewidth. In the normal state, this leads to a Lorentzian shape of the phonon line. Density functional theory is able to predict the phonon linewidths as a function of wave vector for each branch of the phonon dispersion. An experimental verification of such predictions is feasible only for compounds with very strong electron-phonon coupling. YN2B2C was chosen as a test example because it is a conventional superconductor with a fairly high T c (15.2 K). Inelastic neutron scattering experiments did largely confirm the theoretical predictions. Moreover, they revealed a strong temperature dependence of the linewidths of some phonons with particularly strong electron-phonon coupling which can as yet only qualitatively be accounted for by theory. For such phonons, marked changes of the phonon frequencies and linewidths were observed from room temperature down to 15 K. Further changes were observed on entering into the superconducting state. These changes can, however, not be described simply by a change of the phonon linewidth.


Electron-phonon coupling density functional theory inelastic neutron scattering 


63.20.dd 63.20.kd 


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Copyright information

© Indian Academy of Sciences 2008

Authors and Affiliations

  • L. Pintschovius
    • 1
    Email author
  • F. Weber
    • 1
    • 2
  • W. Reichardt
    • 1
  • A. Kreyssig
    • 3
    • 4
  • R. Heid
    • 1
  • D. Reznik
    • 1
    • 5
  • O. Stockert
    • 6
  • K. Hradil
    • 7
  1. 1.Forschungszentrum KarlsruheInstitut für FestkörperphysikKarlsruheGermany
  2. 2.Physikalisches InstitutUniversität Karlsruhe (TH)KarlsruheGermany
  3. 3.Institut für FestkörperphysikTechnische Universität DresdenDresdenGermany
  4. 4.Ames LaboratoryIowa State UniversityAmesUSA
  5. 5.Laboratoire Léon BrillouinCE-SaclayGif-sur-YvetteFrance
  6. 6.Max-Planck-Institut für Chem. Physik fester StoffeDresdenGermany
  7. 7.Institut für physikalische Chemie, Aussenstelle FRM-IIUniversität GöttingenGarchingGermany

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