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Localization of electronic states in amorphous materials: recursive Greens function method and the metal-insulator transition at E<>0

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 نشر من قبل Rudolf A. Roemer
 تاريخ النشر 2006
  مجال البحث فيزياء
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In this paper we will investigate whether the scaling assumptions made in previous studies for the transition at energies outside the band centre can be reconfirmed in numerical calculations, and in particular whether the conductivity sigma follows a power law close to the critical energy E_c. For this purpose we will use the recursive Greens function method to calculate the four-terminal conductance of a disordered system for fixed disorder strength at temperature T=0. Applying the finite-size scaling analysis we will compute the critical exponent and determine the mobility edge, i.e. the MIT outside the band centre.



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