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Non-equilibrium electronic transport and interaction in short metallic nanobridges

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 نشر من قبل Johann Kroha
 تاريخ النشر 2000
  مجال البحث فيزياء
والبحث باللغة English
 تأليف H. B. Weber




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We have observed interaction effects in the differential conductance $G$ of short, disordered metal bridges in a well-controlled non-equilibrium situation, where the distribution function has a double Fermi step. A logarithmic scaling law is found both for the temperature and for the voltage dependence of $G$ in all samples. The absence of magnetic field dependence and the low dimensionality of our samples allow us to distinguish between several possible interaction effects, proposed recently in nanoscopic samples. The universal scaling curve is explained quantitatively by the theory of electron-electron interaction in diffusive metals, adapted to the present case, where the sample size is smaller than the thermal diffusion length.

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