Plasmon modes of a massive Dirac plasma, and their superlattices

TL;DR

This paper analytically investigates the plasmon modes of massive Dirac particles in various dimensions and superlattices, revealing unique density-dependent dispersion relations and potential applications in tunable plasmonic metamaterials.

Contribution

It provides analytical expressions for plasmon dispersion in massive Dirac systems across different dimensions and superlattices, highlighting their distinct density dependence.

Findings

Long wavelength plasmon dispersion differs from parabolic and gapless Dirac systems.

Analytical formulas for 1D, 2D, and 3D massive Dirac plasmons are derived.

Potential for experimental verification via infrared spectroscopy.

Abstract

We explore the collective density oscillations of a collection of charged massive Dirac particles, in one, two and three dimensions and their one dimensional superlattice. We calculate the long wavelength limit of the dynamical polarization function analytically, and use the random phase approximation to obtain the plasmon dispersion. The density dependence of the long wavelength plasmon frequency in massive Dirac systems is found to be different compared to systems with parabolic, and gapless Dirac dispersion. We also calculate the long wavelength plasmon dispersion of a 1d metamaterial made from 1d and 2d massive Dirac plasma. Our analytical results will be useful for exploring the use of massive Dirac materials as electrostatically tunable plasmonic metamaterials and can be experimentally verified by infrared spectroscopy as in the case of graphene [L. Ju. et. al., Nat. Nanotechnol. 6, 630 (2011)].