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

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.

7 pages, 7 figures

References in corpus (12)

• $\alpha$-RuCl3: a Spin-Orbit Assisted Mott Insulator on a Honeycomb Lattice
• Models and Materials for Generalized Kitaev Magnetism
• Scattering Continuum and Possible Fractionalized Excitations in $\alpha$-RuCl${}_3$
• Magnetic order in $\alpha$-RuCl${}_3$: a honeycomb lattice quantum magnet with strong spin-orbit coupling
• Successive magnetic phase transitions in $\mathbf{\alpha }$-RuCl${}_3$: XY-like frustrated magnet on the honeycomb lattice
• Kitaev magnetism in honeycomb RuCl3 with intermediate spin-orbit coupling
• Robustness of the thermal Hall effect close to half-quantization in a field-induced spin liquid state
• The planar thermal Hall conductivity in the Kitaev magnet α-RuCl3
• Sample dependence of the half-integer quantized thermal Hall effect in the Kitaev candidate $\alpha$-RuCl${}_3$
• Evidence of a Phonon Hall Effect in the Kitaev Spin Liquid Candidate $\alpha$-RuCl${}_3$
• Field-induced phase transitions of the Kitaev material $\alpha$-RuCl${}_3$ probed by thermal expansion and magnetostriction
• Origin of oscillatory structures in the magnetothermal conductivity of the putative Kitaev magnet $\alpha$-RuCl${}_3$

Cited by in corpus (1)

• Phonon thermal transport shaped by strong spin-phonon scattering in a Kitaev material Na${}_2$Co${}_2$TeO${}_6$