Investigations of Graphene on SrTiO₃ Single-Crystal using Confocal Raman Spectroscopy

We will present the characterizations of graphene layers placed on SrTiO₃ single-crystal substrates using temperature-dependent confocal Raman spectroscopy. This approach successfully resolved distinct Raman modes of graphene that are often untraceable in conventional measurements due to the strong Raman scattering background of SrTiO₃. Information on defects and strain states was obtained for a few graphene/SrTiO₃ samples that were synthesized by different techniques. This confocal Raman spectroscopic approach can shed light on the investigation of not only this graphene/SrTiO₃ system but also various two-dimensional layered materials whose Raman modes interfere with their substrates.