Raman Spectrum of Graphene and Graphene Layers

Key Points

• To determine how the Raman spectrum of graphene reflects changes in electronic band structure across varying layer thicknesses and evaluate its utility for layer identification.
• Measured Raman spectra across single-layer and multi-layer graphene samples.
• Tracked spectral variations in the second-order D peak and G peak to evaluate electronic band changes driven by double resonant Raman processes.
• The second-order D peak systematically changes in shape, width, and position as the number of graphene layers increases.
• The G peak displays a slight downward frequency shift with increasing layer count, providing a high-throughput, nondestructive method to distinguish layer thickness.