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Quantum Superconductor-Metal Transition in Al, C doped MgB2 and overdoped Cuprates?

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 نشر من قبل Toni Schneider
 تاريخ النشر 2007
  مجال البحث فيزياء
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 تأليف T. Schneider




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We consider the realistic case of a superconductor with a nonzero density of elastic scatterers, so that the normal state conductivity is finite. The quantum superconductor-metal (QSM) transition can then be tuned by varying either the attractive electron-electron interaction, the quenched disorder, or the applied magnetic field. We explore the consistency of the associated scaling relations, Tc ~ 1/lamda(0) ~ gap(0) ~ 1/gsi(0) ~ Hc2(0)^-0.5 and Tc(H) ~ 1/Lamda(0,H) ~ gap(0,h) ~ (Hc2(0)-H)^ 1/2, valid for all dimensions D > 2, with experimental data, in Al, C doped MgB2 and overdoped cuprates.



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