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Spin thermal conductivity of the Haldane chain compound Y2BaNiO5

K. Kordonis·A. V. Sologubenko·T. Lorenz·S. -W. Cheong·A. Freimuth
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Abstract

We have measured the thermal conductivity of the spin S=1 chain compound Y2BaNiO5. Analyzing the anisotropy of the thermal transport allows to identify a definite spin-mediated thermal conductivity κ_s along the chain direction. The calculated spin-related energy diffusion constant D_E(T) shows a broad peak around 120 K. Close to room temperature, D_E(T) approaches the theoretically predicted high-temperature value, while scattering of spin excitations by magnetic impurities seems to be the major limiting factor of κ_s at low temperature.

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K. Kordonis, A. V. Sologubenko, T. Lorenz, S. -W. Cheong, A. Freimuth. 2006-08-15. Spin thermal conductivity of the Haldane chain compound Y2BaNiO5. https://doi.org/10.1103/physrevlett.97.115901

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