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Abstract Moiré potential profile can form flat electronic bands and manifest correlated states of electrons, where carrier doping is essential for observing those correlations. In this work, we uncover a hidden but remarkable many-electron effect: doped carriers form a two-dimensional plasmon and strongly couple with quasiparticles to renormalize moiré potential and realize ultra-flat bands. Using many-body perturbation theory, we demonstrate this effect in twisted MoS₂/WS₂heterobilayer. The moiré potential is significantly enhanced upon carrier doping, and the bandwidth is reduced by order of magnitude, leading to drastic quenching of electronic kinetic energy and stronger correlation. We further predict that the competition between correlated mechanisms can be effectively controlled via doping, giving hope to a quantum transition between Mott and charge-transfer insulating states. Our work reveals that the potential renormalization effect of doping is much more significant in determining and controlling many-electron electronic correlations than sole filling-factor tuning in semiconducting moiré crystals. 

Abstract As a fundamental type of topological spin textures in two-dimensional (2D) magnets, a magnetic meron carries half-integer topological charge and forms a pair with its antithesis to keep the stability in materials. However, it is challenging to quantitatively calculate merons and their dynamics by using the widely used continuum model because of the characteristic highly inhomogeneous spin textures. In this work, we develop a discrete method to address the concentrated spin structures around the core of merons. We reveal a logarithmic-scale interaction between merons when their distance is larger than twice their core size and obtain subsequent statistics of meron gas. The model also predicts how these properties of single and paired merons evolve with magnetic exchange interactions, and the results are in excellent agreement with the Monte Carlo simulations using the parameters of real 2D van der Waals magnetic materials. This discrete approach not only shows equilibrium static statistics of meron systems but also is useful to further explore the dynamic properties of merons through the quantified pairing interactions.