Carrier induced ferromagnetism in Yb doped SrTiO₃ perovskite system

Ferromagnetism induced Yb (1, 3 %) doped SrTiO₃ compounds were synthesized by glycol assisted citrate sol–gel method. The cubic perovskite structure of the prepared compounds was confirmed by powder X-ray diffraction and laser Raman spectra analysis. Surface morphology of the prepared compounds was analyzed by scanning electron microscopy and transmission electron microscopy. Oxidation states with functionalization of elements were identified with X-ray photoelectron spectroscopy. The interesting optical behavior was observed for Yb doped samples, which shows violet–blue emissions in photoluminescence spectra due to interface trapping and Sr defects. The magnetization studies demonstrate that pure SrTiO₃ exhibits characteristic diamagnetism at room temperature and the addition of Yb³⁺ in Sr²⁺ site drives the carrier induced exchange interactions which results the ferromagnetic behavior. Hence the occurrence of tunable diamagnetic to ferromagnetic and reversal ferromagnetic transition with respect to the concentration of dopant at room temperature was identified. From the present investigation, it was observed that the doping of Yb in SrTiO₃ results with new kind of multifunctional material for fabrication of magneto-optical and electronic devices.