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Title: Directive and enhanced spontaneous emission using shifted cubes nanoantenna

Abstract

Recent studies have demonstrated that nano-patch antennas formed by metallic nanocubes placed on top of a metallic film largely enhance the spontaneous emission rate of quantum emitters due to the confinement of the electromagnetic field in the small nanogap cavity. The popularity of this architecture is, in part, due to the ease in fabrication. In this contribution, we theoretically demonstrate that a dimer formed by two metallic nanocubes embedded in a dielectric medium exhibits enhanced emission rate compared to the nano-patch antenna. Furthermore, we compare the directivity and radiation efficiency of both nanoantennas. From these characteristics, we obtained information about the “material efficiency” and the coupling mismatch efficiency between a dipole emitter and the nanoantenna. These quantities provide a more intuitive insight than the Purcell factor or localized density of states, opening new perspectives in nanoantenna design for ultra-directive light emission.

Authors:
; ;  [1]
  1. Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, California 92093-0407 (United States)
Publication Date:
OSTI Identifier:
22598803
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 9; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTENNAS; COMPARATIVE EVALUATIONS; CONFINEMENT; CRYSTAL DEFECTS; DENSITY OF STATES; DIELECTRIC MATERIALS; DIMERS; DIPOLES; EFFICIENCY; ELECTROMAGNETIC FIELDS; EMISSION; FABRICATION; FILMS

Citation Formats

Bahari, B., Tellez-Limon, R., and Kante, B., E-mail: bkante@ucsd.edu. Directive and enhanced spontaneous emission using shifted cubes nanoantenna. United States: N. p., 2016. Web. doi:10.1063/1.4962164.
Bahari, B., Tellez-Limon, R., & Kante, B., E-mail: bkante@ucsd.edu. Directive and enhanced spontaneous emission using shifted cubes nanoantenna. United States. doi:10.1063/1.4962164.
Bahari, B., Tellez-Limon, R., and Kante, B., E-mail: bkante@ucsd.edu. 2016. "Directive and enhanced spontaneous emission using shifted cubes nanoantenna". United States. doi:10.1063/1.4962164.
@article{osti_22598803,
title = {Directive and enhanced spontaneous emission using shifted cubes nanoantenna},
author = {Bahari, B. and Tellez-Limon, R. and Kante, B., E-mail: bkante@ucsd.edu},
abstractNote = {Recent studies have demonstrated that nano-patch antennas formed by metallic nanocubes placed on top of a metallic film largely enhance the spontaneous emission rate of quantum emitters due to the confinement of the electromagnetic field in the small nanogap cavity. The popularity of this architecture is, in part, due to the ease in fabrication. In this contribution, we theoretically demonstrate that a dimer formed by two metallic nanocubes embedded in a dielectric medium exhibits enhanced emission rate compared to the nano-patch antenna. Furthermore, we compare the directivity and radiation efficiency of both nanoantennas. From these characteristics, we obtained information about the “material efficiency” and the coupling mismatch efficiency between a dipole emitter and the nanoantenna. These quantities provide a more intuitive insight than the Purcell factor or localized density of states, opening new perspectives in nanoantenna design for ultra-directive light emission.},
doi = {10.1063/1.4962164},
journal = {Journal of Applied Physics},
number = 9,
volume = 120,
place = {United States},
year = 2016,
month = 9
}
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