Dielectric properties and plasmon modes of gapped momentum systems of different dimensionality

TL;DR

This paper investigates the dielectric properties and plasmon modes of gapped momentum systems across different dimensions, revealing unique dispersion behaviors and potential applications in materials with momentum gaps.

Contribution

It introduces a study of dielectric and plasmon properties in gapped momentum materials across 1D, 2D, and 3D systems, including temperature effects and practical estimations.

Findings

Identification of plasmon modes in gapped momentum systems

Unusual dispersion relations depending on dimensionality

Numerical estimates of absorption coefficients for applications

Abstract

The concept of the energy gap is a fundamental characteristic of the band structure of a material and it determines its physical properties. Formally the energy gap appears in the dispersion relation $E_k$, where the vector $k$ is determined on the whole momentum space. However, today the {\it gapped momentum materials} are in the focus of research in which the so-called {\it momentum or $k$-gap} can emerge, i.e. some lacunae of momentum space are excluded from the domain of the function $E_k$. One of such examples present the non-Hermitian systems. Within the random phase approximation we study the dielectric properties of the momentum gapped materials in one, two and three dimensions for both cases of zero and finite temperatures. We find the corresponding plasmon modes and determine the unusual behavior of the appropriate dispersion relations for each dimensionality. Based on these findings we evaluate the absorption coefficient of gapped momentum media and provide some numerical estimations of its value for the practical applications.