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arXiv · 1104.1514

Low-temperature heat transport of Nd_2CuO_4: Roles of Nd magnons and spin-structure transitions

Z. Y. Zhao·X. M. Wang·B. Ni·Q. J. Li·C. Fan·W. P. Ke·W. Tao·L. M. Chen·X. Zhao·X. F. Sun
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Abstract

We report the magnetic-field dependence of thermal conductivity (κ) of an insulating cuprate Nd_2CuO_4 at very low temperatures down to 0.3 K. It is found that apart from the paramagnetic moments scattering on phonons, the Nd^{3+} magnons can act as either heat carriers or phonon scatterers, which strongly depends on the long-range antiferromagnetic transition and the field-induced transitions of spin structure. In particular, the Nd^{3+} magnons can effectively transport heat in the spin-flopped state of the Nd^{3+} sublattice. However, both the magnon transport and the magnetic scattering are quenched at very high fields. The spin re-orientations under the in-plane field can be conjectured from the detailed field dependence of κ.

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Z. Y. Zhao, X. M. Wang, B. Ni, Q. J. Li, C. Fan, W. P. Ke, W. Tao, L. M. Chen, X. Zhao, X. F. Sun. 2011-04-08. Low-temperature heat transport of Nd_2CuO_4: Roles of Nd magnons and spin-structure transitions. https://doi.org/10.1103/physrevb.83.174518

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