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arXiv · 1105.0924

Critical temperature and Ginzburg region near a quantum critical point in two-dimensional metals

J. Bauer·P. Jakubczyk·W. Metzner
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Abstract

We compute the transition temperature $T_c$ and the Ginzburg temperature $T_{\rm G}$ above $T_c$ near a quantum critical point at the boundary of an ordered phase with a broken discrete symmetry in a two-dimensional metallic electron system. Our calculation is based on a renormalization group analysis of the Hertz action with a scalar order parameter. We provide analytic expressions for $T_c$ and $T_{\rm G}$ as a function of the non-thermal control parameter for the quantum phase transition, including logarithmic corrections. The Ginzburg regime between $T_c$ and $T_{\rm G}$ occupies a sizable part of the phase diagram.

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J. Bauer, P. Jakubczyk, W. Metzner. 2011-05-04. Critical temperature and Ginzburg region near a quantum critical point in two-dimensional metals. https://doi.org/10.1103/physrevb.84.075122

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