In recent years, diluted magnetic oxides (DMOs) have been the best choice to investigate in DMS systems. Both half-metallic ferromagnetism and high spin polarization are necessary characteristics of materials that are utilized in the field of spintronics to build the devices. There is a huge opportunity to investigate new types of DMS and various aspects of their physical properties. DMS systems possess semi-conductive and ferromagnetic properties simultaneously. In the field of spintronics and optoelectronic devices, diluted magnetic semiconductors (DMSs) are of unique importance. Some popular theoretical models are also employed to determine various magnetic parameters. The mechanism such as the oxygen vacancy-based F-center exchange model is considered to understand the enhancement of ferromagnetism in ion irradiated CeO 2 thin films. The saturation magnetization in irradiated thin films is directly correlated to the area under the peak of defect-associated PL emission. All the samples demonstrate room temperature ferromagnetism with magnetic saturation ( M s) up to 14.57 emu/cm 3. Magnetic measurements show an enhancement in magnetic ordering with ion irradiation. The surface morphological images show the modification in the surface roughness with ion irradiation and the re-growth of smaller circular-formed nanoparticles on the surface is observed at the fluence of 5 × 10 11 ions/cm 2.
The broad peaks in the PL spectra are associated with oxygen vacancies and are red-shifted (494–520 nm) with ion fluences. The Gaussian deconvolution of photoluminescence (PL) spectra reveals various defect-associated peaks. Raman measurement also supports the presence of the F 2g phase of CeO 2 and the presence of defect states.
X-ray diffraction analysis of these films confirms the stable fluorite phase of CeO 2 even after the higher fluence of irradiations. These thin films were deposited on Si (111) substrates by the electron-beam evaporation method and irradiated by a 100 MeV O 7+ ion beam with different ion fluences. The present investigation reports the swift heavy ion induced effects on cerium oxide (CeO 2) thin films.
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