Heat transport of the quasi-one-dimensional alternating spin chain material (CH_{3})_{2}NH_{2}CuCl_{3}

Physical review. B, Condensed matter (Impact Factor: 3.66). 10/2011; 84(13). DOI: 10.1103/PhysRevB.84.134429
Source: arXiv


We report a study of the low-temperature heat transport in the
quasi-one-dimensional S = 1/2 alternating antiferromagnetic-ferromagnetic chain
compound (CH_{3})_{2}NH_{2}CuCl_{3}. Both the temperature and magnetic-field
dependencies of thermal conductivity are very complicated, pointing to the
important role of spin excitations. It is found that magnetic excitations act
mainly as the phonon scatterers in a broad temperature region from 0.3 to 30 K.
In magnetic fields, the thermal conductivity show drastic changes, particularly
at the field-induced transitions from the low-field N\'{e}el state to the
spin-gapped state, the field-induced magnetic ordered state, and the spin
polarized state. In high fields, the phonon conductivity is significantly
enhanced because of the weakening of spin fluctuations.

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Available from: WenPao Ke, Sep 01, 2014
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