Spectroscopic Signatures of Electronic Excitations in Raman Scattering in Thin Films of Rhombohedral Graphite

Nano Lett. 2019 Sep 11;19(9):6152-6156. doi: 10.1021/acs.nanolett.9b02196. Epub 2019 Aug 7.

Abstract

Rhombohedral graphite features peculiar electronic properties, including persistence of low-energy surface bands of a topological nature. Here, we study the contribution of electron-hole excitations toward inelastic light scattering in thin films of rhombohedral graphite. We show that, in contrast to the featureless electron-hole contribution toward Raman spectrum of graphitic films with Bernal stacking, the inelastic light scattering accompanied by electron-hole excitations in crystals with rhombohedral stacking produces distinct features in the Raman signal which can be used both to identify the stacking and to determine the number of layers in the film.

Keywords: Raman spectroscopy; Rhombohedral graphite; electronic Raman scattering; graphene; optical absorption; stacking-dependent properties.