Hybrid structures of two distinct materials provide an excellent opportunity to optimize functionalities. We report the realization of wide quantum Hall plateaus in graphene field-effect devices on the LaAlO 3 /SrTiO 3 heterostructures. Well-defined quantized Hall resistance plateaus at filling factors v = ± 2 can be obtained over wide ranges of the magnetic field and gate voltage, e.g., extending from 2 T to a maximum available magnetic field of 9 T. By using a simple band diagram model, it is revealed that these wide plateaus arise from the ultra-large capacitance of the ultra-thin LAO layer acting as the dielectric layer. This is distinctly different from the case of epitaxial graphene on SiC substrates, where the realization of giant Hall plateaus relies on the charge transfer between the graphene layer and interface states in SiC. Our results offer an alternative route towards optimizing the quantum Hall performance of graphene, which may find its ...

中文翻译：

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LaAlO 3 / SrTiO 3异质结构上石墨烯的巨电容诱导宽量子霍尔高原。

两种不同材料的混合结构为优化功能提供了极好的机会。我们报告了在LaAlO 3 / SrTiO 3异质结构上的石墨烯场效应器件中实现宽量子霍尔平台的实现。在宽的磁场和栅极电压范围内（例如，从2 T扩展到最大9 T可用磁场），可以获得在填充因子v =±2时定义明确的量化霍尔电阻平稳段。从模型可以看出，这些宽平台是由用作介电层的超薄LAO层的超大电容引起的。这与SiC衬底上外延石墨烯的情况明显不同，后者实现巨型霍尔高原依赖于石墨烯层与SiC中界面态之间的电荷转移。