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DOE OSTI · 1644679

Electronic structure calculations of twisted multi-layer graphene superlattices

Abstract

Quantum confinement endows two-dimensional (2D) layered materials with exceptional physics and novel properties compared to their bulk counterparts. Although certain two- and few-layer configurations of graphene have been realized and studied, a systematic investigation of the properties of arbitrarily layered graphene assemblies is still lacking. We introduce theoretical concepts and methods for the processing of materials information, and as a case study, apply them to investigate the electronic structure of multi-layer graphene-based assemblies in a high-throughput fashion. We provide a critical discussion of patterns and trends in tight binding band structures and we identify specific layered assemblies using low-dispersion electronic bands as indicators of potentially interesting physics like strongly correlated behavior. A combination of data-driven models for visualization and prediction is used to intelligently explore the materials space. This work more generally aims to increase confidence in the combined use of physics-based and data-driven modeling for the systematic refinement of knowledge about 2D layered materials, with implications for the development of novel quantum devices.

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BibTeXRIS

Tritsaris, Georgios A, Carr, Stephen, Zhu, Ziyan, Xie, Yiqi, Torrisi, Steven B, Tang, Jing, Mattheakis, Marios, Larson, Daniel T, Kaxiras, Efthimios. 2020-06-18. Electronic structure calculations of twisted multi-layer graphene superlattices. https://doi.org/10.1088/2053-1583%2Fab8f62

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36 MATERIALS SCIENCE↗