Distinct moiré textures of in-plane electric polarizations for distinguishing moiré origins in homobilayers

作     者：Hongyi Yu Ziheng Zhou Wang Yao 

作者机构：Guangdong Provincial Key Laboratory of Quantum Metrology and SensingSchool of Physics and AstronomySun Yat-sen University(Zhuhai Campus)Zhuhai 519082China State Key Laboratory of Optoelectronic Materials and TechnologiesSun Yat-sen University(Guangzhou Campus)Guangzhou 510275China Department of PhysicsThe University of Hong KongHong Kong 999077China HKU-UCAS Joint Institute of Theoretical and Computational Physics at Hong KongHong Kong 999077China 

出 版 物：《Science China(Physics,Mechanics & Astronomy)》 (中国科学：物理学、力学、天文学（英文版）)

年 卷 期：2023年第66卷第10期

页      面：121-130页

核心收录：

学科分类：07[理学] 070205[理学-凝聚态物理] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0702[理学-物理学] 

基　　金：support by the National Natural Science Foundation of China(Grant No.12274477) the Department of Science and Technology of Guangdong Province in China(Grant No.2019QN01X061) support by the Research Grant Council of Hong Kong SAR(Grant Nos.AoE/P-701/20,and HKU SRFS2122-7S05) the Guangdong-Hong Kong Joint Laboratory of Quantum Matter。 

主　　题：moirépatterns van der Waals stacking electric polarization hexagonal boron nitride graphene 

摘      要：In binary compound 2D insulators/semiconductors such as hexagonal boron nitride(h BN), the different electron affinities of atoms can give rise to out-of-plane electric polarizations across inversion asymmetric van der Waals interface of near 0° interlayer twisting. Here we show that at a general stacking order where sliding breaks 2π/3-rotational symmetry, the interfacial charge redistribution also leads to an in-plane electric polarization, with a magnitude comparable to that of the out-of-plane ones.The effect is demonstrated in h BN bilayers, as well as in biased graphene bilayers with gate-controlled interlayer charge redistributions. In long wavelength moiré patterns, the in-plane electric polarizations determined by the local interlayer stacking registries constitute topologically nontrivial spatial textures. We show that these textures can be used to distinguish moirépatterns of different origins from twisting, biaxial-and uniaxial-heterostrain, where vector fields of electric polarizations feature Bloch-type merons, Néel-type merons, and anti-merons, respectively. Combinations of twisting and heterostrain can further be exploited for engineering various electric polarization textures including 1D quasiperiodic lattices.