Plasmons and screening in finite-bandwidth 2D electron gas
Mesoscale and Nanoscale Physics
2020-09-16 v2
Abstract
The dynamical and nonlocal dielectric function of a two-dimensional electron gas (2DEG) with finite energy bandwidth is computed within random-phase approximation. For large bandwidth, the plasmon dispersion has two separate branches at small and large momenta. The large momenta branch exhibits negative quasi-flat dispersion. The two branches merge with decreasing bandwidth. We discuss how the maximum energy plasmon mode which resides at energies larger than all particle-hole continuum can potentially open a route to low-loss plasmons. Moreover, we discuss the bandwidth effects on the static screening of the charged and magnetic impurities.
Cite
@article{arxiv.1910.01229,
title = {Plasmons and screening in finite-bandwidth 2D electron gas},
author = {Kaveh Khaliji and Tobias Stauber and Tony Low},
journal= {arXiv preprint arXiv:1910.01229},
year = {2020}
}