Collective modes in nodal line semimetals

TL;DR

This paper investigates the collective excitations in nodal line semimetals, revealing a unique plasmon frequency dependence on electron density that can serve as a diagnostic tool for identifying these materials.

Contribution

It introduces a novel method to detect nodal line semimetals through their collective modes, specifically the density-dependent plasmon frequency behavior.

Findings

Plasmon frequency scales as n^{1/4} in the long wavelength limit.

Distinct band structure signatures can be observed via collective mode measurements.

Provides a theoretical basis for experimental identification of nodal line semimetals.

Abstract

Recently, the nodal line semimetals have attracted considerable interests in condensed matter physics. We show that their distinct band structure can be detected by measuring the collective modes. In particular, we find that the dependence of the plasmon frequency $\omega_p$ on the electron density $n$ follows a $\omega_p \sim n^{1/4}$ law in the long wavelength limit. Our results will be useful in the ongoing search for new candidates of nodal line semimetals.