Fluorescence enhancement factors on optical antennas: enlarging the experimental values without changing the antenna design

TL;DR

This paper investigates how experimental parameters like collection efficiency, quantum yield, and excitation intensity influence the measured fluorescence enhancement factors of optical antennas, emphasizing the importance of proper setup configuration.

Contribution

It highlights that fluorescence enhancement factors are not intrinsic and depend on experimental parameters, providing guidance for accurate measurement and interpretation.

Findings

Enhancement factors are significantly affected by setup parameters.

Improper parameter settings can lead to overestimation of enhancement.

The study uses a nanoaperture with plasmonic corrugations as an example.

Abstract

Plasmonic antennas offer promising opportunities to control the emission of quantum objects. As a consequence, the fluorescence enhancement factor is widely used as a figure of merit for a practical antenna realization. However, the fluorescence enhancement factor is not an intrinsic property of the antenna. It critically depends on several parameters, some of which are often disregarded. In this contribution, I explore the influence of the setup collection efficiency, emitter's quantum yield and excitation intensity. Improperly setting these parameters may significantly alter the enhancement values, leading to potential misinterpretations. The discussion is illustrated by an antenna example of a nanoaperture surrounded by plasmonic corrugations.