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N o v e m b e r 0 5 - 0 6 , 2 0 1 8 | P h i l a d e l p h i a , U S A
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Obesity Summit 2018 & Diabetes Conference 2018 & Laser Photonics Conference 2018 Biomedical Research | ISSN: 0976-1683| Volume 29
3rd INTERNATIONAL OBESITY SUMMIT AND EXPO
&
&
DIABETES, NUTRITION, METABOLISM & MEDICARE
2nd International Conference on
Joint Event on
OF EXCELLENCE
IN INTERNATIONAL
MEETINGS
YEARS
LASER, OPTICS AND PHOTONICS
World Conference on
Giorgio Pettinari , Biomed Res 2018, Volume 29 | DOI: 10.4066/biomedicalresearch-C7-018
NOVEL STRATEGIES FOR
SITE-CONTROLLED QUANTUM EMITTER
FABRICATION
Many of the most advanced applications of semiconductor quantum dots
(QDs) in quantum information technology require a fine control of the
QDs’ position and confinement potential, which are hardly to be achieved with
conventional growth techniques. Here, a novel and versatile approach for the
post-growth fabrication of site-controlled QDs is presented based on a spa-
tially selective incorporation or removal of hydrogen atoms in dilute nitride
structures. Hydrogen incorporation in GaAsN results, indeed, in the formation
of N–H complexes that neutralize all the effects of N on GaAs, including the
N-induced large reduction of the bandgap energy. Therefore, by engineering
the spatial incorporation and/or removal of hydrogen in dilute nitrides it is pos-
sible to attain a spatially controlled modulation of the bandgap energy in the
growth plane and, eventually, to tailor the carrier-confining potential down to a
nm scale, resulting in the fabrication of site-controlled QDs that are able to emit
single photons on demand.
Two different fabrication approaches have been developed to control spatial-
ly the hydrogen incorporation and removal in the system: either a lithograph-
ic-based technique for defining hydrogen opaque masks for the spatial control
of hydrogen incorporation and a laser-assisted spatially selective hydrogen
removal technique that takes advantage of a local N–H complex dissociation
induced within the light spot generated by a scanning near-field optical micro-
scope. Both techniques relies on the peculiar ultra-sharp diffusion profile of
hydrogen in dilute nitrides and allow a control on the hydrogen implantation
and/or removal on a nanometer scale. This novel fabrication technique feature
state-of-the-art position accuracy (up to 20 nm) as well as a fine control on the
emission energy of the realized QDs. The strategy for a deterministic spatial
and spectral coupling of such quantum emitters with photonic crystal cavities
has been also developed.
Biography
Giorgio Pettinari is a researcher at the Institute of
Photonics and Nanotechnologies of the National
Research Council of Italy. He got a PhD in materi-
als science from Sapienza University of Rome (Ita-
ly, 2008) and was an assistant researcher at High
Field Magnet Laboratory of the Radboud University
of Nijmegen (The Netherlands, 2009-2011) and a
Marie Curie Research Fellow at the University of
Nottingham (UK, 2011-2013). His interests range
from the experimental investigation of semicon-
ductor nanostructures to micro- and nano-fabrica-
tion and investigation of innovative photonic and
plasmonic devices. Recently, he developed a novel
strategy for the post-growth fabrication of site-con-
trolled, single-photon emitting quantum dots. Pet-
tinari published more than 40 peer-reviewed orig-
inal papers in academic journals (among which 2
invited review papers), 2 invited book chapters, and
he given more than 20 oral contributions and sem-
inars (7 invited) at international conferences and
research institutes.
Giorgio Pettinari
IFN- CNR, Italy