Effect of retardation on the frequency and linewidth of plasma resonances in a twodimensional disk of electron gas
Abstract
We theoretically analyze dominant plasma modes in a twodimensional disk of electron gas by calculating the absorption of an incident electromagnetic wave. The problem is solved in a selfconsistent approximation, taking into account electromagnetic retardation effects. We use the Drude model to describe the conductivity of the system. The absorption spectrum exhibits a series of peaks corresponding to the excitation of plasma waves. The position and linewidth of the peaks designating, respectively, the frequency and damping rate of the plasma modes. We estimate the influence of retardation effects on the frequency and linewidth of the fundamental (dipole) and axisymmetric (quadrupole) plasma modes both numerically and analytically. We find the net damping rate of the modes to be dependent on not only the sum of the radiative and collisional decays but also their intermixture, even for small retardation. We show that the net damping rate can be noticeably less than that determined by collisions alone.
 Publication:

Physical Review B
 Pub Date:
 May 2021
 DOI:
 10.1103/PhysRevB.103.195431
 arXiv:
 arXiv:2011.00877
 Bibcode:
 2021PhRvB.103s5431Z
 Keywords:

 Condensed Matter  Mesoscale and Nanoscale Physics
 EPrint:
 10 pages, 4 figures