We present Raman spectroscopy experiments on exfoliated α-RuCl3, 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 bilayer samples.
- Andreev Reflection without Fermi Surface Alignment
- Controlling Magnetic and Optical Properties of a van der Waals Crystal