Giant-Capacitance-Induced Wide Quantum Hall Plateaus in Graphene on LaAlO3/SrTiO3 Heterostructures

• 作者: Chang-Gan Zeng Li-Jun Zhu Lin Li Lin-Hai Guo Ran Tao Xiao-Dong Fan Yue-Dong Yan
• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2020,（7）
• 所属期刊栏目: CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES
• 页码范围: 86-91
• 页数: 6页
• 语种: 英文
• DOI: 10.1088/0256-307X/37/7/077301

摘要

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 LaAlO3/SrTiO3 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 2T 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 ultralarge 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 applications in the further development of quantum resistance metrology.