Doubly and triply coupled nanowire antennas

TL;DR

This paper investigates how coupling multiple nanowire antennas affects their optical properties, revealing enhanced polarization effects and potential for controlling emitter polarization through experimental and theoretical analysis.

Contribution

It provides experimental evidence and theoretical analysis of polarization-dependent fluorescence enhancements in coupled nanowire arrays, a novel insight into nanowire antenna interactions.

Findings

Enhanced fluorescence polarization in coupled nanowires

Polarization-dependent fluorescence intensity variations

Dipolar plasmon interactions explain observed phenomena

Abstract

Nanoantenna is one of the most important optical components for light harvesting. In this study, we show experimental evidence of interactions between coupled nanowires by comparing the fluorescence properties of quantum dots on both non-coupled (single) and coupled (double and triple) nanowire arrays. The fluorescence intensities are dependent on the excitation polarization, and most of the emissions are polarized perpendicular to the long axis of the nanowires. It is interesting that both the excitation polarization dependent enhancement and the fluorescence polarization effect are more pronounced for coupled nanowires. Our theoretical analysis indicates the above phenomena can be ascribed to the dipolar plasmon from the nanowire antennas. Our investigations demonstrate a potential method to control the polarization of emitters using coupled nanowire arrays.