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arXiv · 1406.5745

Disorder dependence of the ferromagnetic quantum phase transition

Y. Sang·D. Belitz·T. R. Kirkpatrick
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Abstract

We quantitatively discuss the influence of quenched disorder on the ferromagnetic quantum phase transition in metals, using a theory that describes the coupling of the magnetization to gapless fermionic excitations. In clean systems, the transition is first order below a tricritical temperature T_tc. Quenched disorder is predicted to suppress T_tc until it vanishes for residual resistivities rho_0 on the order of several microOhmcm for typical quantum ferromagnets. We discuss experiments that allow to distinguish the mechanism considered from other possible realizations of a first-order transition.

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Y. Sang, D. Belitz, T. R. Kirkpatrick. 2014-06-26. Disorder dependence of the ferromagnetic quantum phase transition. https://doi.org/10.1103/physrevlett.113.207201

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