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

作　　者：Ran Tao Lin Li Li-Jun Zhu Yue-Dong Yan Lin-Hai Guo Xiao-Dong Fan Chang-Gan Zeng 陶然;李林;朱丽君;严跃冬;郭林海;范晓东;曾长淦(International Center for Quantum Design of Functional Materials(ICQD),Hefei National Laboratory for Physical Sciences at the Microscale,and Synergetic Innovation Center of Quantum Information and Quantum Physics,University of Science and Technology of China,Hefei 230026,China;CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics,and Department of Physics,University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]International Center for Quantum Design of Functional Materials(ICQD),Hefei National Laboratory for Physical Sciences at the Microscale,and Synergetic Innovation Center of Quantum Information and Quantum Physics,University of Science and Technology of China,Hefei 230026,China [2]CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics,and Department of Physics,University of Science and Technology of China,Hefei 230026,China

出　　处：《Chinese Physics Letters》2020年第7期86-91,共6页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos.11974324,11804326 and U1832151);the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No.XDC07010000);the National Key Research and Development Program of China (Grant No.2017YFA0403600);Anhui Initiative in Quantum Information Technologies (Grant No.AHY170000);Hefei Science Center CAS (Grant No.2018HSC-UE014)。

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 ν=±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 ultralarge capacitance of the ultra-thin LAO layer acting as the dielectric layer.This is distinctly different from the case of epitaxial graphene on Si C 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.

关 键 词：quantum REALIZATION dielectric 

分 类 号：O469[理学—凝聚态物理] O613.71[理学—电子物理学]