Monolayer-to-Mesoscale Modulation of the Optical Properties in 2D CrI3 Mapped by Hyperspectral Microscopy

Layer-dependent mechanical properties and enhanced plasticity in the van der Waals chromium trihalide magnets

The mechanical properties of magnetic materials are instrumental for the development of the magnetoelastic theory and the optimization of strain-modulated magnetic devices. In particular, two-dimensional (2D) magnets hold promise to enlarge these concepts into the realm of low-dimensional physics and ultrathin devices. However, no experimental study on the intrinsic mechanical properties of the archetypal 2D magnet family of the chromium trihalides has thus far been performed. Here, we report the room temperature layer-dependent mechanical properties of atomically thin CrI3 and CrCl3, finding that bilayers of CrI3 and CrCl3 have Young's moduli of 62.1 GPa and 43.4 GPa, with the highest sust…

Monolayer-to-mesoscale modulation of the optical properties in 2D CrI3 mapped by hyperspectral microscopy

Magnetic 2D materials hold promise to change the miniaturization paradigm of unidirectional photonic components. However, the integration of these materials in devices hinges on the accurate determination of the optical properties down to the monolayer limit, which is still missing. By using hyperspectral wide-field imaging at room temperature, we reveal a nonmonotonic thickness dependence of the complex optical dielectric function in the archetypal magnetic 2D material CrI3 extending across different length scales: onsetting at the mesoscale, peaking at the nanoscale, and decreasing again down to the single layer. These results portray a modification of the electronic properties of the mat…