Electron-phonon coupling in MgB2: a resistivity study

The normal state resistivity behaviour of single crystal MgB2 theoretically analysed within the framework of classical electron-phonon i.e.. Bloch-Gruneisen model of resistivity. Both acoustic and optical phonon contributes towards the resistivity. Optical phonon yields a relatively larger contribution to the resistivity compared to the contribution of acoustic phonon. Estimated contribution to resistivity by phonons, along with the zero limited resistivity, when subtracted from single crystal data infers a quadratic temperature dependence over most of the temperature range [40 ≤ T ± 300] and understood in terms of electron-electron scattering. A relationship is established in between ρee and carrier density. (author)