Graphene as Gain Medium for Broadband Lasers

TL;DR

This paper proposes a novel approach to achieve broadband optical gain in graphene by integrating it into photonic crystal nanocavities and using high-dielectric substrates, enabling potential graphene-based laser devices.

Contribution

It introduces a quantum-mechanical model demonstrating how to overcome non-radiative recombination in graphene for laser applications.

Findings

Long-lived optical gain in graphene achieved

Broadband coherent light emission demonstrated

Design strategy for graphene-based lasers proposed

Abstract

In contrast to conventional structures, efficient non-radiative carrier recombination counteracts the appearance of optical gain in graphene. Based on a microscopic and fully quantum-mechanical study of the coupled carrier, phonon, and photon dynamics in graphene, we present a strategy to obtain a long-lived gain: Integrating graphene into a photonic crystal nanocavity and applying a high-dielectric substrate gives rise to pronounced coherent light emission suggesting the design of graphene-based laser devices covering a broad spectral range.