Fig. 3.

Layer number dependence of the zero-momentum magnon characteristics. a Raman spectra of the M₁ (intensity multiplied by 20) and M₂ magnons for 1–5 L, 9 L, and 13 L samples. Light yellow and blue shaded areas are the Lorentzian fits for the M₁ and M₂ magnon modes, respectively. The gray triangles highlight the satellite magnon peaks. b Frequency (ω₀, left axis) and lifetime (Γ^–1, right axis) of the M₁ magnon as a function of layer number. c I. I. of the M₁ magnon as a function of layer number with I. I. of the A₁ phonon shown in gray for comparison. d, e Plots for M₂ that are similar to b, c, with I. I. of the A₃ phonon plotted in gray in e for comparison. Error bars in b–e represent the two SEs of fitting parameters in the Lorentzian fits to individual Raman spectra at different thicknesses