2001/06/18 by M. Putti, E. Galleani d'Agliano, D. Marrè +7 · 1 citation
Physics and Astronomy · #cond-mat.supr-con
paper · pdf · doi:10.1140/epjb/e20020050
published as Eur. Phys. J. B 25 439 (2002) · 9 pages, 3 figures
arxiv created 2001/06/18 · arxiv updated 2016/08/15
We have measured the resistivity and the Seebeck coefficient of a MgB2 sintered sample. The temperature dependence of resistivity is fitted well by a generalized Bloch-Gruneisen equation with a Debye temperature of 1050 K. The Seebeck coefficient is given by the sum of a diffusive and a phonon drag term and the behavior in the temperature region % Tc<T<0.1ΘR follows a relationship AT+BT3 where the two terms are proportional to the electron and to the phonon specific heat, respectively. The phonon drag term, here emphasized for the first time, is rather large, indicating a strong electron-phonon interaction. The diffusive term is positive and increases with Al doping. The comparison of the experimental values with calculations including precise electronic structure suggests that σ bands give the main contribution to the Seebeck effect.