Active magneto-optical control of spontaneous emission in graphene

TL;DR

This paper demonstrates how applying a magnetic field to graphene can actively and precisely control the spontaneous emission rates of nearby quantum emitters, enabling significant suppression or enhancement of emission pathways.

Contribution

It introduces a method for active, magnetic-field-based control of quantum emitter decay rates near graphene, highlighting the role of Landau levels in emission modulation.

Findings

Magnetic field can alter decay rates by up to 99% in graphene.

Discontinuous emitter lifetime as a function of magnetic field strength.

Magnetic control enables manipulation of emission pathways in near-field regime.

Abstract

We investigate the spontaneous emission rate of a two-level quantum emitter near a graphene-coated substrate under the influence of an external magnetic field or strain induced pseudo-magnetic field. We demonstrate that the application of the magnetic field can substantially increase or decrease the decay rate. We show that a suppression as large as 99$\%$ in the Purcell factor is achieved even for moderate magnetic fields. The emitter's lifetime is a discontinuous function of $|{\bf B}|$, which is a direct consequence of the occurrence of discrete Landau levels in graphene. We demonstrate that, in the near-field regime, the magnetic field enables an unprecedented control of the decay pathways into which the photon/polariton can be emitted. Our findings strongly suggest that a magnetic field could act as an efficient agent for on-demand, active control of light-matter interactions in graphene at the quantum level.