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arXiv · 1208.1162

Low temperature ballistic spin transport in the S=1/2 antiferromagnetic Heisenberg chain compound SrCuO2

H. Maeter·A. A. Zvyagin·H. Luetkens·G. Pascua·Z. Shermadini·R. Saint-Martin·A. Revcolevschi·C. Hess·B. Büchner·H. -H. Klauss
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Abstract

We report zero and longitudinal magnetic field muon spin relaxation measurements of the spin S=1/2 antiferromagnetic Heisenberg chain material SrCuO2. We find that in a weak applied magnetic field B the spin-lattice relaxation rate follows a power law B^n with n=-0.9(3). This result is temperature independent for 5K < T < 300 K. Within conformal field theory and using the M\"uller ansatz we conclude ballistic spin transport in SrCuO2.

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H. Maeter, A. A. Zvyagin, H. Luetkens, G. Pascua, Z. Shermadini, R. Saint-Martin, A. Revcolevschi, C. Hess, B. Büchner, H. -H. Klauss. 2012-08-06. Low temperature ballistic spin transport in the S=1/2 antiferromagnetic Heisenberg chain compound SrCuO2. https://doi.org/10.1088/0953-8984%2F25%2F36%2F365601

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