Effect Of Phonon Drag On Seebeck Coefficient Based On Linear Response Theory: Application To Fesb2

Based on linear response theory, we study phonon drag effects on Seebeck coefficient beyond Boltzmann transport regime by focusing on the roles of impurity bands with the aim to explore the possible microscopic understanding of unusual behavior observed in FeSb2. We find that the phonon drag in the presence of impurity bands with the narrow band gap below the conduction band with large effective mass will be the key factors behind the remarkable phenomenon.