Magneto-electronic Coulomb excitations in AA-stacked graphite
Rong-Bin Chen1*, Chin-Wei Chiu2, Ming-Fa Lin2
1Center of General Studies, National Kaohsiung Marine, Kaohsiung, Taiwan
2Department of Physics, National Cheng Kung University, Tainan, Taiwan
* presenting author:Rong-Bin Chen, email:rbchen@mail.nkmu.edu.tw
Magneto-electronic Coulomb excitations in AA-stacked graphite are studied within the random-phase approximation. They strongly depend on the direction, the magnitude of the transferred momentum q, and the magnetic field B. The plasmon frequency ω is the function of the transferred momentum along the perpendicular component qz in the primitive unit cell and its parallel component q|| are very different from each other. The former only one prominent peak, ω increases with qz, while the intensity of plasmon peak exhibits the opposite behavior. The latter presents a lot of peaks. As field strength increases, the plasmon peaks are intensified. The group velocity for plasmon propagation along qz-direction is positive for fixed B. Moreover, the qz-dependence of ω is gradually reduced with increasing field strength.


Keywords: graphite, random-phase approximation, magnetic field, dielectric function, collective excitations