Electronic anisotropy in magic-angle twisted trilayer graphene
Electronic anisotropy in magic-angle twisted trilayer graphene
复制标题
魔角扭曲三层石墨烯的电子各向异性
DOI：
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Jia Li
中科院分区：
文献类型：
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作者：
Na Zhang;Yibang Wang;Kenji Watanabe;T. Taniguchi;O. Vafek;Jia Li
由于其与向列性的潜在联系，电子各向异性一直是各种材料平台上激烈研究的主题。空间各向异性的出现不仅提供了传统输运技术无法获得的金属相材料特性的表征，而且还提供了一个独特的窗口，可以了解库仑相互作用和电子秩序下的对称性破缺之间的相互作用。在这项工作中，我们利用一种新的角度分辨输运测量（ARTM）方案来表征魔角扭曲三层石墨烯中的电子各向异性。通过分析空间各向异性对莫尔带填充、温度和扭转角的依赖性，我们建立了电子各向异性与级联现象之间的第一个实验联系，其中库仑相互作用驱动了相应带填充附近的许多同位旋跃迁。此外，我们报告了电子各向异性与打破宇称和时间反转对称性的新电子顺序之间的共存。结合电子各向异性、级联现象和pt对称性破缺之间的联系，揭示了魔角石墨烯莫尔系统中电子秩序的本质。
Due to its potential connection with nematicity, electronic anisotropy has been the subject of intense research effort on a wide variety of material platforms. The emergence of spatial anisotropy not only offers a characterization of material properties of metallic phases, which cannot be accessed via conventional transport techniques, but it also provides a unique window into the interplay between Coulomb interaction and broken symmetry underlying the electronic order. In this work, we utilize a new scheme of angle-resolved transport measurement (ARTM) to characterize electron anisotropy in magic-angle twisted trilayer graphene. By analyzing the dependence of spatial anisotropy on moir'e band filling, temperature and twist angle, we establish the first experimental link between electron anisotropy and the cascade phenomenon, where Coulomb interaction drives a number of isospin transitions near commensurate band fillings. Furthermore, we report the coexistence between electron anisotropy and a novel electronic order that breaks both parity and time reversal symmetry. Combined, the link between electron anisotropy, cascade phenomenon and PT-symmetry breaking sheds new light onto the nature of electronic order in magic-angle graphene moir'e systems.