Adiabatic amplification of plasmons and demons in 2D systems

TL;DR

This paper presents a theoretical study on how time-varying conditions in 2D conductors can lead to amplification of collective modes like plasmons and energy waves, with potential experimental implications.

Contribution

It introduces a new theoretical framework for adiabatic amplification of plasmons and energy waves in 2D systems with hot electrons, applicable to graphene.

Findings

Modes can be losslessly amplified or compensated in 2D conductors.

The theory applies to graphene plasmons and energy waves.

Potential for experimental observation in pump-probe setups.

Abstract

We theoretically investigate charged collective modes in a two-dimensional conductor with hot electrons where the instantaneous mode frequencies gradually increase or decrease with time. We show that the loss compensation or even amplification of the modes may occur. We apply our theory to two types of collective modes in graphene, the plasmons and the energy waves, which can be probed in optical pump-probe experiments.