# Light-matter interaction of a quantum emitter near a half-space graphene nanostructure

## TL;DR

This paper investigates how a quantum emitter's spontaneous emission and light-matter interaction are significantly enhanced near a graphene half-space nanostructure, revealing strong coupling effects and anisotropic behavior.

## Contribution

It provides a semi-analytical study of Purcell enhancement and strong coupling phenomena near graphene nanostructures, highlighting the role of edge and bulk plasmon modes.

## Key findings

- Purcell factor enhanced over eight orders of magnitude at resonance
- Strong light-matter coupling with Rabi splitting of 80 meV
- Anisotropic emission behavior depending on dipole orientation

## Abstract

The Purcell factor and the spontaneous emission spectrum of a quantum emitter (QE) placed close to the edge of a graphene half-space nanostructure is investigated, using semi-analytical methods at the electrostatic regime. The half-space geometry supports an edge and a bulk surface plasmon (SP) mode. The Purcell factor of the QE is enhanced over eight orders of magnitude when its emission energy matches the resonance energy modes, for a specific value of the in-plane wave vector, at a separation distance of $5\,$nm. The different transition dipole moment orientations influence differently the enhancement factor of a QE, leading to large anisotropic behavior when positioned at different places above the half-space geometry. The field distribution is presented, showing clearly the excitation of the SP modes at the edge of the nanostructures. Also, we present the spontaneous emission spectrum of the QE near the half-space graphene nanostructure and show that strong light-matter coupling may emerge. When a QE with a free-space lifetime of $1\,$ns is placed at a distance of $10\,$nm away from the edge of the graphene half-space, a Rabi splitting of $80 \,m$eV is found. Our contribution can be used for designing future quantum applications using combination of QEs and graphene nanostructures.