Perturbations of dipole decay dynamics induced by plasmonic nano-antennas - a study within the discrete dipole approximation

Abstract

We report a discrete dipole approximation approach to analyse the perturbations induced by silver nano-particles on the decay dynamics of a point-like emitter placed in their proximity. Due to the excitation of localized surface plasmons, metallic nano-particles behave like optical antennas and are able to convert localized fields into freepropagating optical radiation, and vice versa. Field localization and enhancement induce strong changes on the decay dynamics of dipoles located in the perturbed electromagnetic environment, and these can be faithfully quantified within the framework of classical electromagnetism in terms of total, radiative and non-radiative decay rates. The method is tested on benchmark cases, i.e., nanospheres and nano-shells, and it is then applied to analytically- unsolvable shapes such as sharp nano-cones and oxide-covered small nano-antennas. Numerical results reveal 105-order enhancements in the total decay rate of the dipole when located very near to the sharp tip, both with and without a thin Ag2O layer. Moreover, the counterintuitive behaviour of the cone response in relation to the distance between the metal and the source of the radiation is discussed. Applications span from strong coupling studies to time-resolved fluorescence spectroscopy.


Autore Pugliese

Tutti gli autori

  • D'Agostino S.; Della Sala F.; Andreani L.C.

Titolo volume/Rivista

Nanomaterials and Nanotechnology


Anno di pubblicazione

2015

ISSN

1847-9804

ISBN

Non Disponibile


Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

Non Disponibile


Numero di citazioni Scopus

Non Disponibile

Ultimo Aggiornamento Citazioni

Non Disponibile


Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile