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

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 نشر من قبل Johannes Bauer
 تاريخ النشر 2011
  مجال البحث فيزياء
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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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