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

TL;DR

This study employs temperature-dependent confocal Raman spectroscopy to analyze graphene on SrTiO3 substrates, revealing defect and strain information despite substrate interference, and demonstrating a method applicable to other 2D materials.

Contribution

The paper introduces a confocal Raman spectroscopy method that effectively isolates graphene signals on SrTiO3, enabling detailed analysis of defects and strain states.

Findings

Resolved Raman modes of graphene on SrTiO3

Detected defect and strain states in graphene samples

Method applicable to other 2D layered materials

Abstract

Graphene layers placed on SrTiO3 single-crystal substrates were investigated 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.