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arXiv · 1709.00431

Possible Structural Transformation and Enhanced Magnetic Fluctuations in Exfoliated $\alpha$-RuCl$_3$

Boyi Zhou·Yiping Wang·Gavin B. Osterhoudt·Paige Kelly·David Mandrus·Rui He·Kenneth S. Burch·Erik A. Henriksen
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Abstract

We present initial Raman spectroscopy experiments on exfoliated flakes of $\alpha$-RuCl$_3$, from tens of nm thick down to single layers. Besides unexpectedly finding this material to be air stable, in the thinnest layers we observe the appearance with decreasing temperature of a symmetry-forbidden mode in crossed polarization, along with an anomalous broadening of a mode at 164 cm$^{-1}$ that is known to couple to a continuum of magnetic excitations. This may be due to an enhancement of magnetic fluctuations and evidence for a distorted honeycomb lattice in single- and bi-layer samples.

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Boyi Zhou, Yiping Wang, Gavin B. Osterhoudt, Paige Kelly, David Mandrus, Rui He, Kenneth S. Burch, Erik A. Henriksen. 2017-09-01. Possible Structural Transformation and Enhanced Magnetic Fluctuations in Exfoliated $\alpha$-RuCl$_3$. https://doi.org/10.1016/j.jpcs.2018.01.026

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