Superconducting and transport electron-phonon coupling constants in YBa2Cu3O7: effect of the interband anisotropy.

Mazin I.I., Liechtenstein A.I., Rodriguez C.O., Jepsen O., Andersen O.K.

Using previously reported first-principle frozen-phonon LDA calculations the authors have calculated the effective superconducting and transport electron-phonon coupling constants. They have taken into account the anisotropy due to the difference between foul bands crossing the Fermi level in YBa2Cu3O7, and found that because the anisotropy influence both electron-phonon coupling constants, but in the opposite direction, the superconducting constant becomes larger than the transport one. The absolute values of the effective coupling constants is close to 2. The superconducting gaps for the different bands vary by nearly an order of magnitude. The authors also discuss how various experiments might have been explained in terms of the interband anisotropy.

Physica C, 209 125-8, 1993.

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