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Cantor Spectra for Double Exchange Model

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 نشر من قبل Masanori Yamanaka
 تاريخ النشر 2000
  مجال البحث فيزياء
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We numerically study energy spectra and localization properties of the double exchange model at irrational filling factor. To obtain variational ground state, we use a mumerical technique in momentum space by ``embedded boundary condition which has no finite size effect a priori. Although the Hamiltonian has translation invariance, the ground state spontaneously exhibits a self-similarity. Scaling and multi-fractal analysis for the wave functions are performed and the scaling indices $alpha$s are obtained. The energy spectrum is found to be a singular continuous, so-called the Cantor set with zero Lebesque measure.



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