Effects of Co implantation in BaTiO3, SrTiO3, and KTaO3

The implantation at elevated temperatures of Co into single-crystal BaTiO 3 (K), SrTiO 3 , or KTaO 3 (Ca), followed by annealing at 700°C, produced ferromagnetic behavior over a broad range of cobalt concentrations. For BaTiO 3 , this process produced magnetic ordering temperatures above 300 K with coercivities ≤70 Oe. The magnetization-temperature (M-T) plots showed a near-linear decrease of magnetization with increasing temperature. No secondary phases were detected within the sensitivity of high-resolution X-ray diffraction. Similar results were observed for both SrTiO 3 and KTaO 3 . Our results are consistent with recent reports of room temperature ferromagnetism in other perovskite systems such as LaBaMnO 3 and theoretical predictions for transition metal doping of BaTiO 3 .

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