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Is a doped Kondo insulator different from doped Silicon?

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 نشر من قبل John DiTusa
 تاريخ النشر 1997
  مجال البحث فيزياء
والبحث باللغة English
 تأليف J. F. DiTusa




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We have observed the metal-insulator transition in the strongly correlated insulator FeSi with the chemical substitution of Al at the Si site. The magnetic susceptibility, heat capacity, and field dependent conductivity are measured for Al concentrations ranging from 0 to 0.08. For concentrations greater than 0.01 we find metallic properties quantitatively similar to those measured in Si:P with the exception of a greatly enhanced quasiparticle mass. Below 2 K the temperature and field dependent conductivity can be completely described by the theory of disordered Fermi Liquids.



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