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Low-Lying Magnetic Excitation of the Shastry-Sutherland Model

K. Totsuka·S. Miyahara·K. Ueda
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Abstract

By using perturbation calculation and numerical diagonalization, low-energy spin dynamics of the Shastry-Sutherland model is investigated paying particular attention to the two-particle coherent motion. In addition to spin-singlet- and triplet bound states, we find novel branches of coherent motion of a bound quintet pair, which are usually unstable because of repulsion. Unusual dispersion observed in neutron-scattering measurements are explained by the present theory. The importance of the effects of phonon is also pointed out.

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K. Totsuka, S. Miyahara, K. Ueda. 2001-01-10. Low-Lying Magnetic Excitation of the Shastry-Sutherland Model. https://doi.org/10.1103/physrevlett.86.520

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