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arXiv · 1203.0461

Origin of the Enhanced Polarization in La and Mg Co-substituted BiFeO3 Thin Film during the Fatigue Process

Qingqing Ke·Amit Kumar·Xiaojie Lou·Kaiyang Zeng·John Wang
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Abstract

We have studied the polarization fatigue of La and Mg co-substituted BiFeO3 thin film, where a polarization peak is observed during the fatigue process. The origin of such anomalous behavior is analyzed on the basis of the defect evolution using temperature-dependent impedance spectroscopy. It shows that the motion of oxygen vacancies (VO..) is associated with a lower energy barrier, accompanied by the injection of electrons into the film during the fatigue process. A qualitative model is proposed to explain the fatigue behavior, which involves the modification of the Schottky barrier upon the accumulation of VO.. at the metal-dielectric interface.

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Qingqing Ke, Amit Kumar, Xiaojie Lou, Kaiyang Zeng, John Wang. 2012-03-02. Origin of the Enhanced Polarization in La and Mg Co-substituted BiFeO3 Thin Film during the Fatigue Process. https://doi.org/10.1063/1.3678636

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