Heterostructures composed of two-dimensional van der Waals (vdW) materials allow highly controllable stacking, where interlayer twist angles introduce a continuous degree of freedom to alter the electronic band structures and excitonic physics. Motivated by the discovery of Mott insulating states and superconductivity in magic-angle bilayer graphene, the emerging research fields of “twistronics” and moiré physics have aroused great academic interests in the engineering of optoelectronic properties and the exploration of new quantum phenomena, in which moiré superlattice provides a pathway for the realization of artificial excitonic crystals. Here we systematically summarize the current achievements in twistronics and moiré excitonic physics, with emphasis on the roles of lattice rotational mismatches and atomic registries. Firstly, we review the effects of the interlayer twist on electronic and photonic physics, particularly on exciton properties such as dipole moment and spin-valley polarization, through interlayer interactions and electronic band structures. We also discuss the exciton dynamics in vdW heterostructures with different twist angles, like formation, transport and relaxation processes, whose mechanisms are complicated and still need further investigations. Subsequently, we review the theoretical analysis and experimental observations of moiré superlattice and moiré modulated excitons. Various exotic moiré effects are also shown, including periodic potential, moiré miniband, and varying wave function symmetry, which result in exciton localization, emergent exciton peaks and spatially alternating optical selection rule. We further introduce the expanded properties of moiré systems with external modulation factors such as electric field, doping and strain, showing that moiré lattice is a promising platform with high tunability for optoelectronic applications and in-depth study on frontier physics. Lastly, we focus on the rapidly developing field of correlated electron physics based on the moiré system, which is potentially related to the emerging quantum phenomena.

由二维范德华 (vdW) 材料组成的异质结构允许高度可控的堆叠，其中层间扭转角度引入连续的自由度来改变电子能带结构和激子物理。受魔角双层石墨烯中莫特绝缘态和超导性发现的推动，“双旋电子学”和莫尔物理等新兴研究领域引起了光电特性工程和新量子现象探索的极大学术兴趣。超晶格为实现人工激子晶体提供了途径。在这里，我们系统地总结了目前在扭转电子学和莫尔激子物理方面取得的成就，重点是晶格旋转失配和原子配准的作用。首先，我们通过层间相互作用和电子能带结构回顾了层间扭曲对电子和光子物理的影响，特别是对激子性质（例如偶极矩和自旋谷极化）的影响。我们还讨论了不同扭转角的 vdW 异质结构中的激子动力学，如形成、传输和弛豫过程，其机制复杂，仍需要进一步研究。随后，我们回顾了莫尔超晶格和莫尔调制激子的理论分析和实验观察。还显示了各种奇异的莫尔效应，包括周期性势、莫尔微带和变化的波函数对称性，这些效应导致激子局域化、出现激子峰和空间交替的光学选择规则。我们进一步介绍了莫尔系统在电场、掺杂和应变等外部调制因素下的扩展特性，表明莫尔晶格是一个具有高可调性的光电应用和前沿物理深入研究的有前途的平台。最后，我们关注基于莫尔系统的快速发展的相关电子物理领域，该领域可能与新兴的量子现象相关。