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Resistivity Exponents in 3D-Dirac Semimetals From Electron-Electron Interaction

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 نشر من قبل Giorgio Sangiovanni
 تاريخ النشر 2020
  مجال البحث فيزياء
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We study the resistivity of three-dimensional semimetals with linear dispersion in the presence of on-site electron-electron interaction. The well-known quadratic temperature dependence of the resistivity of conventional metals is turned into an unusual $T^6$-behavior. An analogous change affects the thermal transport, preserving the linearity in $T$ of the ratio between thermal and electrical conductivities. These results hold from weak coupling up to the non-perturbative region of the Mott transition. Our findings yield a natural explanation for the hitherto not understood large exponents characterizing the temperature-dependence of transport experiments on various topological semimetals.

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