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Spectral properties of the one-dimensional two-channel Kondo lattice model

90   0   0.0 ( 0 )
 نشر من قبل C. I. Ventura
 تاريخ النشر 1999
  مجال البحث فيزياء
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We have studied the energy spectrum of a one-dimensional Kondo lattice, where the localized magnetic moments have SU(N) symmetry and two channels of conduction electrons are present. At half filling, the system is shown to exist in two phases: one dominated by RKKY-exchange interaction effects, and the other by Kondo screening. A quantum phase transition point separates these two regimes at temperature $T = 0$. The Kondo-dominated phase is shown to possess soft modes, with spectral gaps much smaller than the Kondo temperature.

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