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Comment on "Spin Transport properties of the quantum one-dimensional non-linear sigma model"

Subir Sachdev·Kedar Damle
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Abstract

In a recent preprint (cond-mat/9905415), Fujimoto has used the Bethe ansatz to compute the finite temperature, zero frequency Drude weight of spin transport in the quantum O(3) non-linear sigma model in a magnetic field $H \neq 0$. We show here that, contrary to his claims, the results are in accord with earlier semiclassical results (Sachdev and Damle, cond-mat/9610115). We also comment on his 1/N expansion, and show that it does not properly describe the long-time correlations.

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Subir Sachdev, Kedar Damle. 1999-06-03. Comment on "Spin Transport properties of the quantum one-dimensional non-linear sigma model". https://doi.org/10.1143/jpsj.69.2712

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