Fig. 1. Schematic drafts for (a) normal and (b) cross-sectional scattering configurations. The polarization direction of incident laser is along the X axis, while the polarization direction of scattered is along the X and Y axes for parallel (VV) and crossed (VH) scattering geometries, respectively.

Fig. 2. Polarized Raman spectra of the Fe₃O₄ film of 217 nm obtained in the normal [(a) and (b)] and cross-sectional [(c) and (d)] scattering configuration.

Fig. 3. Thickness-dependent peak position and bandwidth (FWHM) of E_g, T2g(2) and A_1g modes.

Fig. 4. Different Raman modes and their corresponding numerically fitted curves. Black circles represent the experimental results, the red lines are the fitting results.

Fig. 5. (a) bandwidth and (b) correlation length for T2g(1) mode as a function of thickness. The inset shows the thickness dependence of the ratio of half-widths at half maximum on low- and high-frequency sides (Γ_l/Γ_h).