Determination of intrinsic lifetime of edge magnetoplasmons

TL;DR

This paper investigates the properties of edge magnetoplasmons in a 2D electronic system under magnetic fields, revealing their intrinsic long lifetime and the conditions under which they form from bulk plasmons.

Contribution

It demonstrates that edge magnetoplasmons have an intrinsic long lifetime and are formed from bulk plasmons isolated by the cyclotron frequency gap.

Findings

Edge magnetoplasmons are mainly in a transverse magnetic mode.

Bulk plasmons remain non-oscillating under magnetic fields.

Edge magnetoplasmons have an intrinsic long lifetime.

Abstract

It is known that peculiar plasmons whose frequencies are purely imaginary exist in the interior of a two-dimensional electronic system described by the Drude model. We show that when an external magnetic field is applied to the system, these bulk plasmons are still non-oscillating and are isolated from the magnetoplasmons by the energy gap of the cyclotron frequency. These are mainly in a transverse magnetic mode and can combine with a transverse electronic mode locally at an edge of the system to form edge magnetoplasmons. With this observation, we reveal the intrinsic long lifetime of edge magnetoplasmons for the first time.