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Spin transport properties of the quantum one-dimensional non-linear sigma model : an application to Haldane gap systems

Satoshi Fujimoto
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Abstract

Spin transport properties of the quantum one-dimensional non-linear sigma model are studied based upon the Bethe ansatz exact solution for the O(3) sigma model and the 1/N-expansion approach for the O(N) sigma model. It is shown that the spin transport at finite temperatures is ballistic and there is no spin diffusion in this system. A possible mechanism for the spin diffusion observed in the NMR experiment of the Haldane gap system AgVP_2S_6 by Takigawa et al. [Phys. Rev. Lett.{\bf 76}, 2173 (1996)] is also discussed. The inclusion of the spin-phonon interaction accounts for the experimental results qualitatively.

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Satoshi Fujimoto. 1999-05-28. Spin transport properties of the quantum one-dimensional non-linear sigma model : an application to Haldane gap systems. https://doi.org/10.1143/jpsj.68.2810

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