Angular Interplay of Nematicity, Superconductivity, and Strange Metallicity in a Moir\'e Flat Band

Naiyuan J. Zhang; Pavel A. Nosov; Ophelia Evelyn Sommer; Yibang Wang; Kenji Watanabe; Takashi Taniguchi; Eslam Khalaf; J. I. A. Li

arXiv · 2503.15767

Angular Interplay of Nematicity, Superconductivity, and Strange Metallicity in a Moir\'e Flat Band

Naiyuan J. Zhang·Pavel A. Nosov·Ophelia Evelyn Sommer·Yibang Wang·Kenji Watanabe·Takashi Taniguchi·Eslam Khalaf·J. I. A. Li

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Abstract

Superconductivity in strongly correlated electron systems frequently exhibits broken rotational symmetry, raising fundamental questions about the underlying order parameter symmetry. In this work, we demonstrate that electronic nematicity--driven by Coulomb-mediated rotational symmetry breaking--serves as a crucial link to understanding the nature of superconductivity. Utilizing a novel framework of angle-resolved measurement, we reveal an interring angular interplay among nematicity, superconductivity, and strange metallicity in magic-angle twisted trilayer graphene. By establishing a direct correlation between the preferred superconducting transport direction and the principal axis of the metallic phase, our findings place strong constrains on the symmetry of the superconducting order parameter. This work introduces a new paradigm for probing the microscopic mechanisms governing superconductivity in strongly interacting two-dimensional systems.

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Naiyuan J. Zhang, Pavel A. Nosov, Ophelia Evelyn Sommer, Yibang Wang, Kenji Watanabe, Takashi Taniguchi, Eslam Khalaf, J. I. A. Li. 2025-03-20. Angular Interplay of Nematicity, Superconductivity, and Strange Metallicity in a Moir\'e Flat Band. https://arxiv.org/abs/2503.15767

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