近日，以色列魏茨曼科学研究所S. Ilani团队实现了通过相互作用重塑的魔角石墨烯的平带成像。相关论文发表在2026年5月6日出版的《自然》杂志上。

量子材料中的电子相互作用从根本上塑造了它们的能带结构，并由此决定了材料中最具吸引力的量子相。魔角扭曲双层石墨烯（MATBG）已成为一个模型体系，其中平带导致了多种此类量子相，但由于缺乏高分辨率的动量空间探测手段，这些能带的精确本质一直难以捉摸。

研究组利用量子扭转显微镜（QTM），以前所未有的动量和能量分辨率，直接成像了MATBG中相互作用的能带。在偏离魔角时，观测到的能带与单粒子理论高度吻合。然而，在魔角处，他们发现能带被相互作用完全改变，在动量空间的不同区域分别表现出轻电子和重电子的特征。在掺杂时，这些轻、重分量之间的相互影响导致了多种显著现象，包括相互作用诱导的带宽重整化、重粒子的类莫特级联以及轻粒子的狄拉克复兴。

研究组还发现了一个与重分量相关的持续低能激发，暗示了一个尚未被解释的新自由度。这些结果揭示了MATBG中电子的双重性质——即其源于同一个拓扑类重费米子平带内不同动量处的电子，从而解决了该体系中长期存在的谜团。更广泛地，该工作确立了QTM作为一种强有力的工具，可用于对传统技术无法企及的量子材料进行高分辨率谱学研究。

附：英文原文

Title: Imaging the flat bands of magic-angle graphene reshaped by interactions

Author: Xiao, J., Inbar, A., Birkbeck, J., Gershon, N., Zamir, Y., Vituri, Y., Taniguchi, T., Watanabe, K., Berg, E., Ilani, S.

Issue&Volume: 2026-05-06

Abstract: Electron interactions in quantum materials fundamentally shape their energy bands and, with them, the material’s most intriguing quantum phases. Magic-angle twisted bilayer graphene (MATBG)1,2,3 has emerged as a model system in which flat bands lead to a variety of such phases, yet the precise nature of these bands has remained elusive owing to the lack of high-resolution momentum-space probes. Here we use the quantum twisting microscope (QTM) to directly image the interacting energy bands of MATBG with unprecedented momentum and energy resolution. Away from the magic angle, the observed bands closely follow the single-particle theory. At the magic angle, however, we observe bands that are completely transformed by interactions, exhibiting light and heavy electronic character at different parts of momentum space. On doping, the interplay between these light and heavy components leads to a variety of notable phenomena, including interaction-induced bandwidth renormalization, Mott-like cascades of the heavy particles and Dirac revivals of the light particles. We also uncover a persistent low-energy excitation tied to the heavy sector, suggesting a new unaccounted degree of freedom. These results resolve the long-standing puzzle in MATBG—the dual nature of its electrons—by showing that it originates from electrons at different momenta within the same topological heavy-fermion-like flat bands. More broadly, our results establish the QTM as a powerful tool for high-resolution spectroscopic studies of quantum materials previously inaccessible to conventional techniques.

DOI: 10.1038/s41586-026-10378-x

Source: https://www.nature.com/articles/s41586-026-10378-x