A Universal Self-Amplification Channel for Surface Plasma Waves

TL;DR

This paper introduces a universal intrinsic amplification mechanism for surface plasma waves in metals, driven by ballistic electron motions and surface interactions, independent of electron collision rates.

Contribution

It develops a theory revealing a universal self-amplification channel for surface plasma waves, unaffected by electronic collision rates and influenced by surface scattering.

Findings

Existence of a universal intrinsic amplification rate $eta_0$ for SPWs

Amplification rate is independent of electron collision rate $1/\tau$

Surface scattering properties affect the amplification rate

Abstract

We present a theory of surface plasma waves (SPWs) in metals with arbitrary electronic collision rate $1/\tau$. We show that there exists a universal intrinsic amplification channel for these waves, as a result of the unique interplay between ballistic electronic motions and the metal surface. The corresponding intrinsic amplification rate $\gamma_0$ is shown to be independent of $\tau$. We also study its dependence on surface scattering properties.