Quantum emitter in a plasmonic field: an orientation generalised model

TL;DR

This paper develops a generalized theoretical model for the interaction between a quantum emitter and a plasmonic nanoparticle, accounting for arbitrary dipole orientations, which enhances understanding of hybrid nanosystems in quantum optics.

Contribution

It introduces a generalized semi-classical model for quantum emitter-plasmonic interactions at any dipole orientation, extending previous models limited to specific alignments.

Findings

The total field on the quantum emitter varies with dipole orientation.

Intermediate angles lead to non-alignment of the total and external fields.

Implications for optical manipulation and quantum control are discussed.

Abstract

When a quantum emitter (QE) is placed in close proximity to a plasmonic metal nanoparticle (MNP) within an external optical field, a dipole-dipole coupling arises, resulting in a highly tunable hybrid nanosystem that surpasses the optical manipulation capabilities of the individual components. These hybrid systems enable the exploration and manipulation of optical fields at the intersection between classical and quantum phenomena. Theoretical models of this interaction have typically been limited to the extreme orientations, where the QE and plasmonic dipoles are polarised either along or perpendicular to the inter-particle axis, for analytical tractability. In this work, we generalise the semi-classical optical dipole-dipole interaction model for a two-level quantum emitter in a plasmonic field for arbitrary polarisation angles. We show that the total field experienced by the quantum emitter at intermediate angles does not necessarily align with the external input field and discuss the implications of varying the polarisation angle of the external input field.