【摘 要】
：
The low-temperature magnetic order behaviors of perovskite oxide CaCu3Ti4O12 (CCTO) ceramics prepared by dif-ferent methods are discussed.X-ray diffraction,scanning electron microscope,x-ray photoelectron spectroscopy,and direct current (DC) magnetization
【机 构】
：
Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power,Shanghai 20
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The low-temperature magnetic order behaviors of perovskite oxide CaCu3Ti4O12 (CCTO) ceramics prepared by dif-ferent methods are discussed.X-ray diffraction,scanning electron microscope,x-ray photoelectron spectroscopy,and direct current (DC) magnetization are used to characterize the structures,microscopic morphologies,valence states,and magnetic properties of the samples.The results show that the magnetic behaviors of CCTO ceramics are very sensitive to the prepa-ration process.The quenched CCTO ceramic and CCTO powders grown in a molten salt crystal,which contain much more oxygen vacancies and Ti3+,show the coexistence of weak ferromagnetic order and antiferromagnetic order below the Neel temperature.It suggests that the bound magnetopolaron formed by oxygen vacancies and Ti3+ ion composite defects are responsible for the weak ferromagnetic order at low temperature.
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