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Diffusive energy transport in the S=1 Haldane chain compound AgVP2S6

A. V. Sologubenko·S. M. Kazakov·H. R. Ott·T. Asano·Y. Ajiro
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Abstract

We present the results of measurements of the thermal conductivity $κ$ of the spin S=1 chain compound AgVP_2S_6 in the temperature range between 2 and 300 K and with the heat flow directed either along or perpendicular to the chain direction. The analysis of the anisotropy of the heat transport allowed for the identification of a small but non-negligible magnon contribution $κ_m$ along the chains, superimposed on the dominant phonon contribution $κ_ph$. At temperatures above about 100 K the energy diffusion constant D_E(T), calculated from the $κ_m(T)$ data, exhibits similar features as the spin diffusion constant D_S(T), previously measured by NMR. In this regime, the behaviour of both transport parameters is consistent with a diffusion process that is caused by interactions inherent to one-dimensional S=1 spin systems.

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A. V. Sologubenko, S. M. Kazakov, H. R. Ott, T. Asano, Y. Ajiro. 2003-07-16. Diffusive energy transport in the S=1 Haldane chain compound AgVP2S6. https://doi.org/10.1103/physrevb.68.094432

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