Quantum Emitters near Layered Plasmonic Nanostructures: Decay Rate Contributions

TL;DR

This paper presents a numerical method to analyze how quantum emitters decay near layered plasmonic nanostructures, distinguishing between radiation, Ohmic losses, and surface plasmon polaritons, with applications to gap-plasmon resonators.

Contribution

A novel numerical framework combining Huygen's principle and near-field to far-field transformation for decay rate analysis near layered plasmonic structures.

Findings

Decay rates strongly depend on emitter position and orientation.

Different decay channels can be separately quantified.

Radiation patterns and SPP excitation directivity are characterized.

Abstract

We introduce a numerical framework for calculating decay rate contributions when excited two-level quantum emitters are located near layered plasmonic nanostructures, particularly emphasizing the case of plasmonic nanostructures atop metal substrates where three decay channels exist: free space radiation, Ohmic losses, and excitation of surface plasmon polaritons (SPPs). The calculation of decay rate contributions is based on Huygen's equivalence principle together with a near-field to far-field transformation of the local electric field, thereby allowing us to discern the part of the electromagnetic field associated with free propagating waves rather than SPPs. The methodology is applied to the case of an emitter inside and near a gap-plasmon resonator, emphasizing strong position and orientation dependencies of the total decay rate, contributions of different decay channels, radiation patterns, and directivity of SPP excitation.