Abstract Multiferroic BiFeO 3 (BFO) thin films and nanodots are deposited on highly oriented pyrolytic graphite (HOPG) substrates via a pulsed laser deposition technique, where the HOPG surface has a honeycomb lattice structure made of carbon atoms, similar to graphene. A graphene/BFO/HOPG capacitor exhibited multiferroic properties, namely ferroelectricity (a residual polarization of 26.8 μC/cm 2 ) and ferromagnetism (a residual magnetization of 1.1 × 10 −5 emu). The BFO thin film had high domain wall energies and demonstrated switching time of approximately 82 ns. An 8-nm BFO nanodot showed a typical piezoelectric hysteresis loop with an effective residual piezoelectric constant of approximately 110 pm/V and exhibited two clearly separated current curves depending on the ferroelectric polarization direction.

中文翻译：

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在高度取向的热解石墨基底上生长的多铁性 BiFeO 3 薄膜和纳米点

摘要 多铁性 BiFeO 3 (BFO) 薄膜和纳米点通过脉冲激光沉积技术沉积在高度取向的热解石墨 (HOPG) 基底上，其中 HOPG 表面具有由碳原子构成的蜂窝晶格结构，类似于石墨烯。石墨烯/BFO/HOPG 电容器表现出多铁性，即铁电性（剩余极化为 26.8 μC/cm 2 ）和铁磁性（剩余磁化强度为 1.1 × 10 -5 emu）。BFO 薄膜具有高畴壁能量，并展示了大约 82 ns 的开关时间。8-nm BFO 纳米点显示出典型的压电磁滞回线，有效残余压电常数约为 110 pm/V，并根据铁电极化方向显示出两条明显分离的电流曲线。