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arXiv · 2004.08209

Dimension-and lattice-diversified Coulomb excitations in3D,2D,1D-nanotube electron gases,graphene and carbon nanotube

Cheng-Hsueh Yang·Chiun-Yan Lin·Chih-Wei Chiu·Chang-Ting Liu·Ming-Fa Lin
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Abstract

Elementary electronic excitations, which are due to the Coulomb-field scatterings, present the diverse phenomena in 3D, 2D, 1D-nanotube electron gases, graphene and carbon nanotubes. The critical mechanisms cover the dimension-dependent bare Coulomb potentials, energy dispersions, and free/valence carrier density. They are responsible for the main features, the available excitation channels (the electron-hole regions), the joint van Hove singularities, the undamped/damped collective excitations at small/sufficiently high transferred momenta, the momentum dependences of plasmon frequencies (acoustic and optical modes), and their categories (the intraband and inter-pi-band plasmons). There exists certain significant similarities and difference among various systems. The (momentum/ angular momentum, frequency)-excitation phase diagrams are directly reflected in the propagation of plasma waves.

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Cheng-Hsueh Yang, Chiun-Yan Lin, Chih-Wei Chiu, Chang-Ting Liu, Ming-Fa Lin. 2020-04-13. Dimension-and lattice-diversified Coulomb excitations in3D,2D,1D-nanotube electron gases,graphene and carbon nanotube. https://arxiv.org/abs/2004.08209

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