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arXiv · 2201.09959

Acoustic phonon dispersion of $\alpha$-RuCl$_3$

Blair W. Lebert·Subin Kim·Danil A. Prishchenko·Alexander A. Tsirlin·Ayman H. Said·Ahmet Alatas·Young-June Kim
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Abstract

Acoustic phonons have recently been posited as playing an integral role in explaining the half-quantized thermal Hall effect in $\alpha$-RuCl$_3$. Therefore, we present much needed inelastic x-ray scattering measurements of its acoustic phonon dispersion, along with calculations using the frozen-phonon method. We also discuss a temperature study which conclusively shows a first-order structural transition to a non-$C2/m$ space group at low temperature. Together these results are an important backbone for future theoretical and experimental studies of $\alpha$-RuCl$_3$.

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Blair W. Lebert, Subin Kim, Danil A. Prishchenko, Alexander A. Tsirlin, Ayman H. Said, Ahmet Alatas, Young-June Kim. 2022-01-24. Acoustic phonon dispersion of $\alpha$-RuCl$_3$. https://doi.org/10.1103/physrevb.106.l041102

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