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Register a new userTowards a unified description of metallic transport
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Understanding metallic behaviour is still one of the central tasks in Condensed Matter Physics. Recent developments have energized the interest in several modern concepts, such as strange metal, bad metal, and Planckian metal. However, a unified description of metallic resistivity applicable to the existing diversity of materials is still missing. Herein we present an empirical analysis of a large variety of metals, from normal metals to strongly correlated metals, using the same phenomenological approach. The electrical resistivity in all the cases follows a parallel resistor formalism, which takes both T-linear and T-quadratic dependence of the scattering rates into account. The results reveal the significance of the model by showing that the different metallic classes are determined by the relative magnitude of these two components. Importantly, our analysis shows that the T-linear term arises from the Planckian dissipation limit and it is present in all considered systems. This formalism extends previous reports on strange and normal metals, facilitating the classification of materials with non-linear resistivity curves, an important step towards the experimental confirmation of the universal character of the Planckian dissipation bound.
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