Raman scattering study of lattice and electronic excitations in Ce₂O₃^*

The giant magnetodielectric effect exhibited by Ce₂O₃ near T_N suggests the presence of strong electron-lattice coupling effects. To clarify the microscopic details of these effects, we present a temperature and magnetic field dependent Raman scattering study of the lattice and electronic excitations in Ce₂O₃. Two crystal field excitations (CFEs) are observed at low temperatures, corresponding to transitions within the crystal-field-split J=5/2 manifold. We provide evidence that electron-phonon coupling is significantly enhanced at low temperatures, leading to a mixing of electronic and phononic states. The magnetic field-dependence of these coupled excitations provide insight into the microscopic mechanism associated with magnetodielectric behavior in Ce₂O₃.