Study of Electrical Resistivity of Fe-Based Superconducting Compounds

Abstract. The resistivity of Fe-Based superconductor (LaFeAs) was analyzed theoretically, with a focus on its temperature dependence. The resistivity was analyzed using the electron-phonon model, specifically the Bloch-Gruneisen model. We derived the Debye temperature and Einstein temperature from an overlap repulsive potential, it was found that optical phonons have a greater impact on resistivity than acoustic phonons at certain higher temperatures while acoustic phonons dominate below that temperature. By considering acoustic and optical phonons with zero limited resistivity, the total resistivity was calculated which shoes a quadratic temperature dependence. The contribution of electron-electron inelastic scattering was found by dependence of ñdiff.= [ ñexp - {ñ0 + ñe-ph (= ñac + ñop)}]. The analysis supports the use of the BG electron-phonon model for this system. Kresin's strong coupling theory was used to calculate the superconducting transition temperature and isotope effect exponent, which suggest that the electron-phonon interaction is an important factor in the pairing mechanism.