Theory of the giant plasmon enhanced second harmonic generation in graphene and semiconductor two-dimensional electron systems

TL;DR

This paper develops an analytical theory for the nonlinear electromagnetic response of 2D electron systems, showing giant plasmon-enhanced second harmonic generation especially in graphene compared to traditional semiconductor systems.

Contribution

It provides a self-consistent-field theoretical framework for second harmonic generation in 2D materials, highlighting the significant enhancement in graphene due to plasmon resonance effects.

Findings

Second harmonic generation in graphene is about 100 times stronger than in GaAs quantum wells.

Plasmon resonance conditions can increase the second harmonic intensity by several orders of magnitude.

The theory applies to both semiconductor 2D systems and graphene, offering insights into nonlinear optical responses.

Abstract

An analytical theory of the nonlinear electromagnetic response of a two-dimensional (2D) electron system in the second order in the electric field amplitude is developed. The second-order polarizability and the intensity of the second harmonic signal are calculated within the self-consistent-field approach both for semiconductor 2D electron systems and for graphene. The second harmonic generation in graphene is shown to be about two orders of magnitude stronger than in GaAs quantum wells at typical experimental parameters. Under the conditions of the 2D plasmon resonance the second harmonic radiation intensity is further increased by several orders of magnitude.