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Exact dynamical structure factor of the degenerate Haldane-Shastry model

Takashi Yamamoto·Yasuhiro Saiga·Mitsuhiro Arikawa·Yoshio Kuramoto
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Abstract

The dynamical structure factor $S(q,ω)$ of the K-component (K = 2,3,4) spin chain with the 1/r^2 exchange is derived exactly at zero temperature for arbitrary size of the system. The result is interpreted in terms of a free quasi-particle picture which is generalization of the spinon picture in the SU(2) case; the excited states consist of K quasi-particles each of which is characterized by a set of K-1 quantum numbers. Divergent singularities of $S(q,ω)$ at the spectral edges are derived analytically. The analytic result is checked numerically for finite systems.

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Takashi Yamamoto, Yasuhiro Saiga, Mitsuhiro Arikawa, Yoshio Kuramoto. 1999-12-14. Exact dynamical structure factor of the degenerate Haldane-Shastry model. https://doi.org/10.1103/physrevlett.84.1308

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