Figure 2.

(a) Raman spectra of 30 nm Cr₂Ge₂Te₆ under different conditions at 300 K. (b) Raman spectra of Ca₂RuO₄ with two magnetic geometries (B_1g and A_g scattering) under various temperatures. (c) Low-frequency polarized Raman spectra of monolayer NiPS₃. (d) Polarized Raman spectra of 10 nm MnPS₃ with θ = 0. (e) Photoluminescence spectra of monolayer CrI₃ for σ⁺ (red) and σ⁻ (blue) circularly polarized photoluminescence with the application of an out-of-plane magnetic field at 15 K. The center panel is the plotting of circular polarization (ρ) dependence on the applied magnetic field. (f) Temperature-dependent Kerr rotation intensities of Cr₂Ge₂Te₆ with varying thickness under a perpendicular field ~0.075 T. (g) Experimental (blue squares) and theoretical (red dotted lines) field-dependent T_C of Cr₂Ge₂Te₆ with varying thickness. Panel (a) is reproduced with permission from ref. [26], copyright 2016 2D Materials. Panel (b) is reproduced with permission from ref. [27], copyright 2017 Physical Review Letters. Panel (c) is reproduced with permission from ref. [29], copyright 2019 Nature Communications. Panel (d) is reproduced with permission from ref. [31], copyright 2017 ACS Nano. Panel (e) is reproduced with permission from ref. [33], copyright 2017 Nature Physics. Panel (f, g) are reproduced with permission from ref. [13], copyright 2017 Letter.