title: Electronic transport in the Coulomb phase of the pyrochlore spin ice.
abstract: We investigate the transport properties of itinerant electrons interacting with a background of localized spins in a correlated paramagnetic phase of the pyrochlore lattice. We find a residual resistivity at zero temperature due to the scattering of electrons by the static dipolar spin-spin correlation that characterizes the metallic Coulomb phase. As temperature increases, thermally excited topological defects, also known as magnetic monopoles, reduce the spin correlation, hence suppressing electron scattering. Combined with the usual scattering processes in metals at higher temperatures, this mechanism yields a nonmonotonic resistivity, displaying a minimum at temperature scales associated with the magnetic monopole excitation energy. Our calculations agree quantitatively with resistivity measurements in Nd(2)Ir(2)O(7) and Pr(2)Ir(2)O(7), shedding light on the origin of the resistivity minimum observed in metallic spin-ice compounds.
authors.affiliation: Theoretical Division, T-4 and CNLS, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA and Department of Physics, University of Wisconsin, Madison, Wisconsin 53706, USA.
authors.forename: Gia-Wei
authors.initials: GW
authors.lastname: Chern
authors.affiliation: Department of Physics, University of Wisconsin, Madison, Wisconsin 53706, USA.
authors.forename: Saurabh
authors.initials: S
authors.lastname: Maiti
authors.affiliation: School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Rafael M
authors.initials: RM
authors.lastname: Fernandes
authors.affiliation: Institute for Condensed Matter Theory and Institute for Nanotechnology, Karlsruhe Institute of Technology, D-76128 Karlsruhe, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Wölfle