title: Non-Kondo mechanism for resistivity minimum in spin ice conduction systems.
abstract: We present a mechanism of resistivity minimum in conduction electron systems coupled with localized moments, which is distinguished from the Kondo effect. Instead of the spin-flip process in the Kondo effect, electrons are elastically scattered by local spin correlations which evolve in a particular way under geometrical frustration as decreasing temperature. This is demonstrated by the cellular dynamical mean-field theory for a spin-ice-type Kondo lattice model on a pyrochlore lattice. Peculiar temperature dependences of the resistivity, specific heat, and magnetic susceptibility in the non-Kondo mechanism are compared with the experimental data in metallic Ir pyrochlore oxides.
authors.affiliation: Department of Applied Physics, University of Tokyo, Tokyo, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Udagawa
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ishizuka
authors.forename: Yukitoshi
authors.initials: Y
authors.lastname: Motome