▎ 摘　　要

The frequency shift of the Raman G peak of epitaxial graphene due to the interaction with a substrate described by effective bond force constant k is investigated using the model of two coupled oscillators. The relative G-peak shift is shown to be Delta omega(G)/omega(G) alpha k/k(0g), where k(0g) is the bond-stretching force constant of single-layer graphene. Assuming k alpha P and k alpha-T, where P and T are the pressure and temperature, and the k variation to be dominant, we qualitatively explain the experimental dependences of Delta omega(G) on P and T. The effect of the substrate on the G-peak broadening in epitaxial graphene is discussed.