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arXiv · 2303.11308

Thermal decomposition of the Kitaev material $\alpha$-RuCl$_3$ and its influence on low-temperature behavior

Franziska A. Breitner·Anton Jesche·Vladimir Tsurkan·Philipp Gegenwart
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Abstract

We explore the effect of heat treatment in argon atmosphere under various temperatures up to $500^\circ$C on single crystals of $\alpha$-RuCl$_3$ by study of the mass loss, microprobe energy dispersive x-ray spectroscopy, powder x-ray diffraction, electrical resistance as well as low-temperature magnetic susceptibility and specific heat. Clear signatures of dechlorination and oxidation of Ru appear for annealing temperatures beyond $300^\circ$C. Analysis of the specific heat below 2~K reveals a RuO$_2$ mass fraction of order $1\%$ for pristine $\alpha$-RuCl$_3$ which increases up to $20\%$ after thermal annealing, fully consistent with mass-loss analysis. The small RuO$_2$ inclusions drastically reduce the global electrical resistance and may thus significantly affect low-temperature thermal transport and Hall effect.

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Franziska A. Breitner, Anton Jesche, Vladimir Tsurkan, Philipp Gegenwart. 2023-03-20. Thermal decomposition of the Kitaev material $\alpha$-RuCl$_3$ and its influence on low-temperature behavior. https://doi.org/10.1103/physrevb.108.045103

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