講題:Single-particle and collective excitations in layered graphenes 摘要:The generalized .. tight-binding model and the random-phase approximation are developed and combined together to fully the many-particle Coulomb interactions in 2D graphene systems. The intralayer & interlayer hopping integrals, the intralayer & interlayer Coulomb interactions, electric field, and magnetic field are taken into account simultaneously. The electron-hole excitations and plasmon modes are very sensitive to the number of layers, stacking configurations, doping levels, and external fields. Apparently, the (momentum, frequency)-phase diagrams exhibit the diverse Coulomb excitation phenomena. Part of theoretical predictions are consistent with the EELS measurements, while most of them require the further examinations. The dimensionless energy loss functions, being clearly characterized in the current work, are very useful in the near-future studies on (i) the time-dependent plasmon propagation on the 2D planes and (ii) the layer-related Coulomb decay rates. |

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