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Interplay between incommensurate phases in the cuprates

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 نشر من قبل Raymond Fresard
 تاريخ النشر 2006
  مجال البحث فيزياء
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We establish the qualitative behavior of the incommensurability $epsilon$, optimal domain wall filling $ u$ and chemical potential $mu$ for increasing doping by a systematic slave-boson study of an array of vertical stripes separated by up to $d=11$ lattice constants. Our findings obtained in the Hubbard model with the next-nearest neighbor hopping $t=-0.15t$ agree qualitatively with the experimental data for the cuprates in the doping regime $xlesssim 1/8$. It is found that $t$ modifies the optimal filling $ u$ and triggers the crossover to the diagonal (1,1) spiral phase at increasing doping, stabilized already at $xsimeq 0.09$ for $t=-0.3t$.

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