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Page 27
allied
academies
August 23-24, 2018 | Paris, France
Laser, Optics and Photonics
International Conference on
Journal of Materials Science and Nanotechnology | Volume: 2
AlGaAs on insulator second-order nonlinear nanophotonics
Guiseppe Leo
1
, C Gigli
1
, G Marino
1
, A Lemaitre
2
, M Celebrano
3
, D Neshev
4
and
C De Angelis
5
1
Paris Diderot University, France
2
C2N, CNRS, France
3
Politecnico di Milano, Italy
4
Nonlinear Physics Centre, Australia
5
University of Brescia, Italy
A
ll-dielectric nonlinear meta-optics is attracting a great
deal of interest thanks to the feasibility of high refractive-
index contrast nanostructures available with semiconductor
lithography. While χ
(3)
effects have been reported in silicon-
on-insulator nanoantennas the AlGaAs-on-insulator platform
has recently enabled the demonstration of second harmonic
generation (SHG) in χ
(2)
nanoantennas. When one excites them
with a plane wave at normal incidence, they exhibit efficient
SHG driven by a magnetic-dipole resonance at the pump
frequency in the optical telecom range and a polarisation
behaviour dominated by a high-order multipole resonance at
the second harmonic. Here we will illustrate our recent activity
on Al
0.18
Ga
0.82
As-on-AlOx nonlinear nanoantennas, where AlOx
is obtained from selective wet etching of micrometer-thick
aluminium-richAlGaAsepitaxiallayer.Suchalowrefractiveindex
substrateallowstoeffectivelydecouplethenanoantennamodes
from the underlying GaAs (100) wafer. After an introduction
on the technology, we will get across the SHG performance
of single nanoantennas with circular Bragg gratings, hybrid
nanoantennas, and nanoantenna dimers exhibiting an anapole
behaviour.Allourexperimentalresultsareobtainedwithapump
excitation around 1.55µm on nanostructures of different size.
The measured SHG conversion efficiency, in excess of 10-5 for
a 1.6GW/cm
2
pump intensity, as well as the related polarization
and radiation diagram properties, paves the way to the
engineering of nanoantennas towards nonlinear meta surfaces.
Speaker Biography
Giuseppe Leo coordinates the Nonlinear Photonics Group of the MPQ Laboratory
at Paris Diderot University. Besides editing 1 book and registering 4 patents, he has
published more than 100 articles on peer-reviewed journals, 10 book chapters and
about250conferencepapers,givingseveral invitedpresentationsatmajor international
conferences.Hish-indexis26,foratotalnumberofcollectedcitationsofmorethan2000.
e:
giuseppe.leo@univ-paris-diderot.frNotes: