Talk about naniantennas
Alan Aspuru-Guzik
(Sent from my mobile phone and might contain typos. Thanks for
understanding.)
Begin forwarded message:
From: "Marko Loncar"
<loncar(a)seas.harvard.edu>
Date: October 9, 2009 7:21:03 EDT
To: <aspuru(a)chemistry.harvard.edu>
Subject: FW: Schedule for Dal Negro
Reply-To: <loncar(a)seas.harvard.edu>
-----Original Message-----
From: Marko Loncar [mailto:loncar@seas.harvard.edu]
Sent: Friday, October 09, 2009 7:10 AM
To: 'alan(a)aspuru.com'.com'; 'Eric Mazur'
Cc: 'Virginia Casas'
Subject: FW: Schedule for Dal Negro
Hi guys,
Would you be interested in meeting today's EE seminar speaker, Luca
Dal
Negro from Boston Univ.?
He has been doing excellent work in different areas, and today he
will be
talking about aperiodic structures for sensing (abstract below). I
figured
this is of interest to you.
His seminar is at 3pm in Maxwell Dworkin G125.
If the time slots that are open don't work for you, please let me
know. Luca
can come earlier and stay longer.
Also, feel free to join us for lunch at noon at Faculty Club (Federico
Capasso may join us as well).
Lastly, if you cannot meet with Luca, can you have your guys show
him your
labs etc? Please advertise your talk in your groups so that we can
have nice
attendance :)
Thanks!
Marko
---
DETERMINISTIC APERIODIC STRUCTURES
FOR NANOPHOTONICS AND SENSING APPLICATIONS
Luca Dal Negro
Department of Electrical and Computing Engineering & Photonics
Center
Boston University, 8 Saint Mary's street, Room 825
Boston, MA 02215-2421 USA
Deterministic Aperiodic Structures (DAS) are generated by the
mathematical
rules of L-systems and number theory, manifest unique light
localization and
transport properties associated with a great structural complexity,
and can
be fabricated on-chips using conventional nano-lithographic
techniques. When
combined with metal-dielectric nanostructures, they give rise to large
energy gaps like periodic media (i.e. photonic-plasmonic crystals) and
highly localized, enhanced field states like disordered random media,
including the formation of Anderson-localized modes, forbidden in
periodic
scattering media. However, contrary to random media, DAS possess
controllable transport properties from ballistic to anomalous
diffusion
(slower diffusion than classical random walks) and strongly
localized field
states with large fluctuations of the photonic mode density -
essential
attributes to achieve spatio-temporal energy localization and to
enhanced
light-matter coupling, i.e. radiative rates of fluorescent molecules,
absorption cross-sections, non-linear optical processes on the
nanoscale. In
particular, DAS fabricated using metal/dielectric nanoparticles can be
utilized to develop novel nanophotonics structures for a variety of
technological applications, including Surface Enhanced Raman (SERS)
sensing,
optical detectors, and enhanced light-emitting and nonlinear
components for
nanoplasmonics.
In this talk, by combining dark-field scattering characterization,
micro-photoluminescence and near-field optical measurements with
accurate
electrodynamics calculations based on semi-analytical scattering
theories, I
will discuss electromagnetic coupling1,2, resonant scattering3,
colorimetric
sensing4, light emission and enhanced Raman scattering5 in two-
dimensional
metal-dielectric arrays based on deterministic aperiodic sequences. In
particular, I will focus on the broadband plasmonic scattering and
localization properties of Fibonacci, Thue-Morse and Rudin-Shapiro
lattices
fabricated by Electron-Beam Lithography (EBL) on transparent quartz
substrates.
Finally, I will consider the design of novel plasmonic DAS ideally
suited
for broadband light emission enhancement and energy harvesting on
chip-scale
devices capable of producing the behavior of purely random systems
to an
arbitrary degree of accuracy.
Luca Dal Negro received both the Laurea in physics, summa cum laude,
in
1999 and the Ph.D. degree in semiconductor physics from the
University of
Trento, Italy, in 2003. After his Ph.D., in 2003 he joined MIT as a
post
doctoral associate.
Since January 2006 he is Assistant Professor in the Department of
Electrical
and Computer Engineering at Boston University and a Photonics Center
faculty
member. He manages and conducts research projects on silicon-based
photonic
materials and devices, plasmon sensing and complex photonic media.
His main
interests are currently on light-emitting silicon nanostructures,
aperiodic
and fractal optics, nano-plasmonics and computational
electromagnetics. He
has authored and coauthored more than 80 technical articles and
received
several Awards including the NSF Career Award, the Young Italian
Scientist
Award, and the Dean's Catalyst Award at Boston University.