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On the Ordering Instability of Weakly-Interacting Electrons in a Dirty Metal

Chetan Nayak·Xiao Yang
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Abstract

In a dirty metal, electron-electron interactions in the spin-triplet channel lead to singular corrections to a variety of physical quantities. We show that these singularities herald the emergence of ferromagnetism. We calculate the effective action for the magnetic moment of weakly-interacting electrons in a dirty metal and show that a state with finite ferromagnetic moment minimizes this effective action. The saddle-point approximation is exact in an appropriate large-N limit. We discuss the physics of the ferromagnetic state with particular regard to thermal fluctuations and localization effects.

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Chetan Nayak, Xiao Yang. 2003-02-25. On the Ordering Instability of Weakly-Interacting Electrons in a Dirty Metal. https://doi.org/10.1103/physrevb.68.104423

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