Plasmons and screening in finite-bandwidth 2D electron gas

29 Feb 2020  ·  Khaliji Kaveh, Stauber Tobias, Low Tony ·

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. read more

PDF Abstract
No code implementations yet. Submit your code now

Categories


Mesoscale and Nanoscale Physics