Role of Dirac cones in magnetotransport properties of REFeAsO (RE = rare earth) oxypnictides

In this work we study the effect of the rare earth element in iron oxypnictides of composition REFeAsO (RE=rare earth). On one hand we carry out density functional theory calculations of the band structure, which evidence the multiband character of these compounds and the presence of Dirac cones along the Y-Γ and Z-R directions of the reciprocal space. On the other hand, we explore transport behavior by means of resistivity, Hall resistance and magnetoresistance measurements, which confirm the dominant role of Dirac cones. By combining our theoretical and experimental approaches, we extract information on effective masses, scattering rates and Fermi velocities for different rare earth elements. Copyright EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2013