近日，美国宾夕法尼亚大学的Ritesh Agarwal及其研究团队取得一项新进展。经过不懈努力，他们揭示三维螺旋晶格中的光-扭曲电子学霍尔效应。相关研究成果已于2024年9月18日在国际权威学术期刊《自然》上发表。

本文研究了基于多层WS₂自组装扭曲螺旋超晶格的三维扭曲电子学。这项研究结果表明，由结构手性和相干长度驱动的光-扭曲霍尔效应，受到螺旋超晶格莫尔势的调制。这是该系统非交换几何性质的实验表现。研究人员观察到了增强的光-物质相互作用，以及霍尔系数对光子动量的改变依赖性。

这项研究模型表明，高阶量子几何量对这一观测结果有贡献，为设计具有大非线性的基于量子材料的光电子晶格提供了机遇。

据悉，对莫尔系统的研究已经解释了超晶格调制对其性质的影响，并展示了新的关联相。然而，大多数实验研究都集中在二维系统的少数几层上。由于手动堆叠层所面临的挑战，将扭曲电子学扩展到三维（即扭曲延伸到第三维），仍然是一个未被充分探索的领域。

附：英文原文

Title: Opto-twistronic Hall effect in a three-dimensional spiral lattice

Author: Ji, Zhurun, Zhao, Yuzhou, Chen, Yicong, Zhu, Ziyan, Wang, Yuhui, Liu, Wenjing, Modi, Gaurav, Mele, Eugene J., Jin, Song, Agarwal, Ritesh

Issue&Volume: 2024-09-18

Abstract: Studies of moiré systems have explained the effect of superlattice modulations on their properties, demonstrating new correlated phases. However, most experimental studies have focused on a few layers in two-dimensional systems. Extending twistronics to three dimensions, in which the twist extends into the third dimension, remains underexplored because of the challenges associated with the manual stacking of layers. Here we study three-dimensional twistronics using a self-assembled twisted spiral superlattice of multilayered WS₂. Our findings show an opto-twistronic Hall effect driven by structural chirality and coherence length, modulated by the moiré potential of the spiral superlattice. This is an experimental manifestation of the noncommutative geometry of the system. We observe enhanced light–matter interactions and an altered dependence of the Hall coefficient on photon momentum. Our model suggests contributions from higher-order quantum geometric quantities to this observation, providing opportunities for designing quantum-materials-based optoelectronic lattices with large nonlinearities.

DOI: 10.1038/s41586-024-07949-1

Source: https://www.nature.com/articles/s41586-024-07949-1