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Low-energy excitations in a one-dimensional orthogonal dimer model with the Dzyaloshinski-Moriya interaction

Kenji Sasaoka·Chikara Ishii
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Abstract

Effects of the Dzyaloshinski-Moriya (DM) interaction on low-energy excitations in a one-dimensional orthogonal-dimer model are studied by using the perturbation expansions and the numerical diagonalization method. In the absence of the DM interaction, the triplet excitations show two flat spectra with three-fold degeneracy, which are labeled by magnetization $M=0,\pm{1}$. These spectra split into two branches with M=0 and with $M=\pm{1}$ by switching-on of the DM interaction and besides the curvature appears in the triplet excitations with $M=\pm 1$ more strongly than those of M=0.

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Kenji Sasaoka, Chikara Ishii. 2004-10-02. Low-energy excitations in a one-dimensional orthogonal dimer model with the Dzyaloshinski-Moriya interaction. https://doi.org/10.1016/j.jpcs.2005.05.032

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