The effect of interband interactions of phonon and charge fluctuation on the superconducting parameters of MgB₂

Abstract

We have investigated the effect of unconventional pairing mechanism in MgB2 using a two-band model within the framework of Bogoliubov-Valatin formalism. The approach incorporates the intraband s-wave interaction in the s-and p-bands, as well as interband s-wave interaction between them. The analysis assumes the pairing interaction matrix comprises of attractive electron-phonon, charge fluctuation and repulsive electron-electron (Coulomb) interactions to account for superconductivity in MgB2. The model is used to estimate the transition temperature and isotope effect exponent as well as to elucidate the importance of interband contributions in the superconductivity of the system. Published version: Supercond. Sci. Technol. 23, 045031 (2010).

EPW: Electron–phonon coupling, transport and superconducting properties using maximally localized Wannier functions

“…The anisotropic gap arises from the σ and π Fermi-surface sheets [10,[151][152][153][154][155]. This superconductor has been widely investigated theoretically [10,90,151,[156][157][158][159][160][161][162][163][164][165][166][167] due to its high T c . We re-investigate here MgB 2 using EPW to show that its fascinating properties can now be computed easily and accurately.…”

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