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Ferromagnetism in one-dimensional metals: breakdown of the Hartree-Fock approximation and possible first order phase transition

Philipp Zedler·Peter Kopietz
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Abstract

We calculate the Gibbs potential Gamma (M) of a one-dimensional metal at constant magnetization M to second order in the screened electron-electron interaction U. At zero temperature we find that Gamma (M) contains non-analytic corrections proportional to M^2 \ln | M| and | M |^3, implying that a possible paramagnetic-ferromagnetic quantum phase transition in one-dimensional metals must be first order.

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Philipp Zedler, Peter Kopietz. 2005-08-18. Ferromagnetism in one-dimensional metals: breakdown of the Hartree-Fock approximation and possible first order phase transition. https://doi.org/10.1103/physrevb.72.184404

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