We conducted an in-depth experimental investigation into the electronic Raman scattering signature by employing energy- and power-dependent Raman spectroscopy with different laser excitations in the polycrystalline La modified $\mathrm{Ce}{\mathrm{O}}_2$ ($\mathrm{C}{\mathrm{e}}_{1–x}\mathrm{L}{\mathrm{a}}_x{\mathrm{O}}_2$) system. At a resonant energy of 2.33 eV, which approximately corresponds to the electronic transition at or from Ce $4f$ empty defect states or more specifically $F_{5/2}$ and $F_{7/2}$ in $\mathrm{C}{\mathrm{e}}_{1–x}\mathrm{L}{\mathrm{a}}_x{\mathrm{O}}_2$ samples, photoexcited electrons are stimulated from the defect state near the Fermi level. This, in turn, manifests the electronic Raman scattering signature within the Raman spectra. Consequently, under resonance conditions, the line shape ($F_{2g}$) associated with $\mathrm{Ce}-{\mathrm{O}}_8$ lattice vibrations becomes symmetric. However, under off-resonance laser excitation, it becomes asymmetric. We have elucidated this phenomenon by modeling electron-phonon interactions using the Fano model. Furthermore, we observed a nonuniform increase in the low wave number background with increasing laser power in the normalized spectra. This observation may be attributed to an increase in electronic scattering by delocalized electrons near the Fermi level, which could subsequently couple with nearby phonons. We have analyzed this effect by fitting the background of Raman spectra using a mathematical model. The major cause for the electronic Raman scattering in a $\mathrm{Ce}{\mathrm{O}}_2$-based system is the presence of unpaired $f$ electrons in the $4f$ empty defect level of $\mathrm{Ce}{\mathrm{O}}_2$-based systems. This study provides valuable insights into electronic Raman spectroscopy of oxide-based semiconductors with defects, particularly when utilizing a range of laser excitations.

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• Defects
• Electron-phonon coupling
• Doped semiconductors
• Wide band gap systems
• Raman spectroscopy