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arXiv · 1201.0929

Non-Kondo mechanism for resistivity minimum in spin ice conduction systems

Masafumi Udagawa·Hiroaki Ishizuka·Yukitoshi Motome
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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.

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Masafumi Udagawa, Hiroaki Ishizuka, Yukitoshi Motome. 2012-01-05. Non-Kondo mechanism for resistivity minimum in spin ice conduction systems. https://doi.org/10.1103/physrevlett.108.066406

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