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Phonon dispersion and electron-phonon interaction for YBa_2Cu_3O_7 from first-principles calculations

K. -P. Bohnen·R. Heid·M. Krauss
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Abstract

We present a first principles investigation of the lattice dynamics and electron-phonon coupling of the high-T_c superconductor YBa_2Cu_3O_7 within the framework of density functional perturbation theory using a mixed-basis pseudopotential method. The calculated phonon dispersion curves are in excellent agreement with Raman, infrared and neutron data. Calculation of the Eliashberg function alpha^2F leads to a small electron-phonon coupling lambda=0.27 in disagreement with earlier approximate treatments. Our calculations strongly support the view that conventional electron-phonon coupling is not an important contribution to superconductivity in high-T_c materials.

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K. -P. Bohnen, R. Heid, M. Krauss. 2002-11-05. Phonon dispersion and electron-phonon interaction for YBa_2Cu_3O_7 from first-principles calculations. https://doi.org/10.1209/epl%2Fi2003-00143-x

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