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arXiv · 1406.6541

Probing electronic excitations in mono- to pentalayer graphene by micro-magneto-Raman spectroscopy

Stéphane Berciaud·Marek Potemski·Clément Faugeras
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Abstract

We probe electronic excitations between Landau levels in freestanding $N-$layer graphene over a broad energy range, with unprecedented spectral and spatial resolution, using micro-magneto Raman scattering spectroscopy. A characteristic evolution of electronic bands in up to five Bernal-stacked graphene layers is evidenced and shown to remarkably follow a simple theoretical approach, based on an effective bilayer model. $(N>3)$-layer graphene appear as appealing candidates in the quest for novel phenomena, particularly in the quantum Hall effect regime. Our work paves the way towards minimally-invasive investigations of magneto-excitons in other emerging low-dimensional systems, with a spatial resolution down to 1$~μ$m.

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Stéphane Berciaud, Marek Potemski, Clément Faugeras. 2014-07-05. Probing electronic excitations in mono- to pentalayer graphene by micro-magneto-Raman spectroscopy. https://doi.org/10.1021/nl501578m

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