Band structure determines the motion of electrons in a solid, giving rise to exotic phenomena when properly engineered. Drawing an analogy between electrons and photons, artificially designed optical lattices indicate the possibility of a similar band modulation effect in graphene systems. Yet due to the fermionic nature of electrons, modulated electronic systems promise far richer categories of behaviors than those found in optical lattices. Here, we uncovered a strong modulation of electronic states in bilayer graphene subject to periodic potentials. We observed for the first time the hybridization of electron and hole sub-bands, resulting in local band gaps at both primary and secondary charge neutrality points. Such hybridization leads to the formation of flat bands, enabling the study of correlated effects in graphene systems. This work may provide a novel way to manipulate electronic states in layered systems, which is important to both fundamental research and application.

中文翻译：

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双层石墨烯中的电子空穴杂化

能带结构决定了电子在固体中的运动，如果设计得当，会产生奇异的现象。在电子和光子之间进行类比，人工设计的光学晶格表明石墨烯系统中可能存在类似的带调制效应。然而，由于电子的费米子性质，调制电子系统有望提供比光学晶格中发现的行为种类更丰富的行为。在这里，我们发现了受周期性电位影响的双层石墨烯中电子状态的强调制。我们首次观察到电子和空穴子带的杂化，导致在初级和次级电荷中性点处产生局部带隙。这种杂交导致形成平坦带，从而能够研究石墨烯系统中的相关效应。