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Anomalous dynamical scaling from nematic and U(1)-gauge field fluctuations in two dimensional metals

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 نشر من قبل Tobias Holder
 تاريخ النشر 2015
  مجال البحث فيزياء
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We analyze the scaling theory of two-dimensional metallic electron systems in the presence of critical bosonic fluctuations with small wave vectors, which are either due to a U(1) gauge field, or generated by an Ising nematic quantum critical point. The one-loop dynamical exponent z=3 of these critical systems was shown previously to be robust up to three-loop order. We show that the cancellations preventing anomalous contributions to z at three-loop order have special reasons, such that anomalous dynamical scaling emerges at four-loop order.

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