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Effect of a Staggered Magnetic Field on the S=1 Haldane Chain with Single-ion Anisotropy

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 نشر من قبل Marco Roncaglia
 تاريخ النشر 2002
  مجال البحث فيزياء
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We analyze the gaps in the excitation spectrum of a Haldane chain with single-ion anisotropy in a staggered field. We show that the gap along the direction of the field increases at a faster rate than the others, while its spectral weight decreases, being transferred to a two-magnon continuum.

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