Figure 1.

(a)Low temperature structure of CrI₃ in the $R\overline{3}$ space group. (b) Optical microscopy of bulk S0 sample (thickness ~100 μm) and cross-section of S2 sample (thickness ~2 μm). (c) Transmission electron microscopy (TEM) image of S3 sample in Cu grid along with the low-loss and core-loss electron energy loss spectra (EELS) taken from top right area marked by red circle. The thickness of S3 was calculated from the low-loss EELS based on log-ratio method in Digital Micrograph program to be 44 nm. The average thickness for many areas measured is 49 ± 8 nm.