SCIentIFIC RepoRtS | (2018) 8:3415 | DOI:10.1038/s41598-018-21664-8
Coupling a single solid-state
quantum emitter to an array of
resonant plasmonic antennas
, Paola Atkinson
, Armando Rastelli
, Oliver G. Schmidt
, Harald Giessen
& Klas Lindfors
Plasmon resonant arrays or meta-surfaces shape both the incoming optical eld and the local density
of states for emission processes. They provide large regions of enhanced emission from emitters and
greater design exibility than single nanoantennas. This makes them of great interest for engineering
optical absorption and emission. Here we study the coupling of a single quantum emitter, a self-
assembled semiconductor quantum dot, to a plasmonic meta-surface. We investigate the inuence
of the spectral properties of the nanoantennas and the position of the emitter in the unit cell of the
structure. We observe a resonant enhancement due to emitter-array coupling in the far-eld regime and
nd a clear dierence from the interaction of an emitter with a single antenna.
Plasmon resonant nanoparticles enable propagating light elds to be converted into localized energy and vice
. Due to this property they are called optical antennas. Optical antennas allow the impedance between a
subwavelength light source, such as a semiconductor quantum dot (QD), and free space to be matched, resulting
in increased emission
. Optical antennas also enable the radiation pattern to be shaped
and the polarization
of the emission to be modied
, making them an interesting tool to control light-emission from single quan-
In order to signicantly modify the spontaneous decay of a quantum emitter using optical antennas, the
emitter has to be placed in the near-eld of the plasmonic nanostructure. For quantum emitters buried in a
substrate such as self-assembled semiconductor quantum dots or nitrogen-vacancy centers in a diamond crystal
this requires the emitters to be placed very close to the substrate surface. is oen results in degradation of the
optical properties of the emitters due to surface states
. Additionally, the plasmonic nanostructure has to be
positioned or fabricated with extremely high spatial accuracy with respect to the quantum emitter, which is oen
. A promising alternative to optical antennas to control light emission from emitters that may
resolve these challenges is optical metasurfaces
. Here plasmonic antennas are arranged in arrays
controlling the spatial distribution of the amplitude, polarization, and phase of the electromagnetic eld with sub-
wavelength spatial resolution
. In plasmonic nanoantenna arrays there exist large regions of enhanced emission
and absorption in the unit cells of the array, so that position dependence of the coupling is less critical
could be highly desirable for plasmonic emission enhancement for organic optoelectronic devices and other thin
lm structures. In this study we investigate the coupling of single self-assembled semiconductor quantum dots to
arrays of plasmon resonant nanoantennas. We observe modications of the emission when the optical resonance
of the array is tuned to the emission energy of the emitters, and demonstrate enhanced emission for quantum dots
placed in the array outside of the near- and intermediate-zones of the plasmonic antennas.
We prepare rectangular arrays of plasmonic gold nanorod antennas with varying aspect ratio on the surface of a
crystal containing near-surface GaAs quantum dots (see Fig.1a). Each plasmonic nanoantenna array has an area
Department of Chemistry, University of Cologne, Luxemburger Str. 116, D-50939 Köln, Germany.
Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart, Germany.
Fourth Physics Institute
and Research Center SCoPE, University of Stuttgart, Pfaenwaldring 57, D-70550 Stuttgart, Germany.
for Integrative Nanosciences, IFW Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany.
Universites, UPMC Univ Paris 06, CNRS, UMR 7588, Institut des Nanosciences de Paris, 4 place Jussieu, F-75252,
Experimental Physics III, University of Bayreuth, Universitätsstrasse 30, D-95447 Bayreuth, Germany.
Correspondence and requests for materials should be addressed to M.L. (email: email@example.com)
or K.L. (email: firstname.lastname@example.org)
Received: 30 November 2017
Accepted: 8 February 2018
Published: xx xx xxxx