Doubled Moiré fat bands in double-twisted few-layer graphite  

作　　者：Zhen Ma Shuai Li Ming Lu Dong-Hui Xu Jin-Hua Gao XinCheng Xie 

机构地区：[1]School of Physics,Wuhan National High Magnetic Field Center,Huazhong University of Science and Technology,Wuhan 430074,China [2]Beijing Academyof Quantum Information Sciences,Beijing100193,China [3]International Center for Quantum Materials,School of Physics,Peking University,Beijing 100871,China [4]Department of Physics and Chongqing Key Laboratory for Strongly Coupled Physics,Chongqing University,Chongqing 400044,China [5]Center of Quantum Materials and Devices,Chongqing University,Chongqing 400044,China [6]CAS Center for Excellence in Topological Quantum Computation,University of Chinese Academy of Sciences,Beijing 100190,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2023年第2期95-101,共7页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 11874160, 12141401, and 11534001);the National Key Research and Development Program of China (Grant No. 2017YFA0403501);the Fundamental Research Funds for the Central Universities (Grant No. HUST:2017KFYXJJ027);supported by the National Basic Research Program of China (Grant No.2015CB921102);the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB28000000)。

摘　　要：We study the electronic structure of double-twisted few-layer graphite(DTFLG),which consists of three few-layer graphites(FLGs),i.e.,an ABA-stacked graphene multilayer,stacked with two twist angles.We consider two categories of DTFLG,the alternately and chirally twisted cases,according to the rotation direction of the two twist angles.We show that,once the middle FLG of DTFLG is not thinner than the trilayer,both types of DTFLG can remarkably host two pairs of degenerate Moire flat bands(MFBs) at EF,twice that of the magic angle twisted bilayer graphene(TBG).The doubled MFBs of DTFLG lead to a doubled density of states(DOS) at the Fermi level EF,which implies much stronger correlation effects than TBG.The degeneracy of MFBs can be lifted by a perpendicular electric field,and the isolated MFBs have a nonzero valley Chern number.We also reveal the peculiar wave function patterns of the MFB s in DTFLG.Our results establish a new family of Moire systems that have a much higher DOS at EFand thus possibly much stronger correlation effects.

关 键 词：TWISTED BANDS doubled 

分 类 号：TQ424[化学工程]