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arXiv · 2005.10721

Electronic Raman Scattering in Twistronic Few-Layer Graphene

A. Garcia-Ruiz·J. J. P. Thompson·M. Mucha-Kruczynski·V. I. Fal'ko
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Abstract

We study electronic contribution to the Raman scattering signals of two-, three- and four-layer graphene with layers at one of the interfaces twisted by a small angle with respect to each other. We find that the Raman spectra of these systems feature two peaks produced by van Hove singularities in moir\'{e} minibands of twistronic graphene, one related to direct hybridization of Dirac states, and the other resulting from band folding caused by moir\'{e} superlattice. The positions of both peaks strongly depend on the twist angle, so that their detection can be used for non-invasive characterization of the twist, even in hBN-encapsulated structures.

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A. Garcia-Ruiz, J. J. P. Thompson, M. Mucha-Kruczynski, V. I. Fal'ko. 2020-05-21. Electronic Raman Scattering in Twistronic Few-Layer Graphene. https://doi.org/10.1103/physrevlett.125.197401

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