Applicability of Landauer formalism on transport properties of Fe-based high-Tc superconductors

The thermoelectric and transport properties of the iron-based superconductors (FeSe) are analyzed; we have estimated the contributions due to phonons and electrons toward the thermal conductivity ([Formula: see text], the electronic conductivity ([Formula: see text], the Seebeck coefficient ([Formula: see text] and the thermoelectric figure of merit (ZT) within the linear approach using the Landauer formalism. The thermoelectric power [Formula: see text] and its temperature dependence for the FeSe superconductor are anomalous. Thermoelectric properties are also sensitive to chemical potential ([Formula: see text]) and carrier concentration in the system. The temperature-dependent thermal conductivity [Formula: see text] shows a broad peak near 80[Formula: see text]K; this is because of numerous operating scattering processes of phonons and electrons. A balance between phonon contribution to thermal conductivity ([Formula: see text] and electron contribution to thermal conductivity ([Formula: see text] determines the anomalies observed in transport properties. The combined effect of all the above transport parameters finally determines the thermoelectric figure of merit (ZT) in these materials.