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arXiv · 1408.3865

Quantum criticality in two dimensions and Marginal Fermi Liquid

K. B. Efetov
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Abstract

Kinetic properties of a two dimensional model of fermions interacting with antiferromagnetic spin excitations near the quantum critical point (QCP) are considered. The temperature or doping are assumed to be sufficiently high, such that the pseudogap does not appear. In contrast to standard spin-fermion models, it is assumed that there are intrinsic inhomogeneities in the system suppressing space correlations of the antiferromagnetic excitations. It is argued that the inhomogeneities in the spin excitations in the "strange metal" phase can be a consequence of existence of $\pi $-shifted domain walls in the doped antiferromagnetic phase. Averaging over the inhomogeneities and calculating physical quantities like resistivity and some others one can explain unusual properties of cuprates unified under the name "Marginal Fermi Liquid" (MFL). The dependence of the slope of the linear temperature dependence of the resistivity on doping is compared with experimental data.

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K. B. Efetov. 2014-08-17. Quantum criticality in two dimensions and Marginal Fermi Liquid. https://doi.org/10.1103/physrevb.91.045110

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